Kinds Of Estrogens Research Articles

Cucurbit[8]uril-mediated SERS plasmonic nanostructures with sub-nanometer gap for the identification and determination of estrogens.

The SERS intensity of analytes is primarily influenced by the density and distribution of hotspots, which are often difficult to manipulate or regulate. In this study, cucurbit[8]uril (CB[8]), a kind of rigid macrocyclic molecule, was introduced to achieve ~ 1-nm nanogap between gold nanoparticles to increase the density of SERS hotspots. Three kinds of estrogens (estrone (E1), bisphenol A (BPA), and hexestrol (DES)) which are molecules with weak SERS signals were targeted in the hotspots by CB[8] to further improve the sensitivity and selectivity of SERS. It was demonstrated that CB[8] can link gold nanoparticles together through carbonyl groups. In addition, the host-guest interaction of CB[8] and estrogens was proved from the nuclear magnetic resonance hydrogen and infrared spectra. In the presence of CB[8], the SERS intensities of E1, BPA, and DES were increased to 19-fold, 74-fold, and 4-fold, respectively, and the LOD is 3.75µM, 1.19µM, and 8.26µM, respectively. Furthermore, the proposed SERS method was applied to actual milk sample analysis with recoveries of E1 (85.0 ~ 112.8%), BPA (83.0 ~ 103.7%), and DES (62.6 ~ 132.0%). It is expected that the proposed signal enlarging strategy can be applied to other analytes after further development.

Opposite estrogen effects of estrone and 2-hydroxyestrone on MCF-7 sensitivity to the cytotoxic action of cell growth, oxidative stress and inflammation activity

There are many kinds of estrogens, and endogenous estrogens produce a variety of estrogen metabolites with similar structure but with different physiological effects after metabolism in vivo. Studies have shown that estrone (E1) widely occurs in the environment and animal-derived food. Because of its estrogen effect, E1 can have adverse effects on the human body as an endocrine disruptor. In this study, we found that E1 and 2-hydroxyestrone (2-OH-E1), the hydroxylation metabolite of estrogen, have opposite proliferative effects on breast cancer cells (MCF-7) through cell proliferation experiments and comparison of their effects by molecular docking and detection of ROS, Ca2+, and cell pathway proteins. The effects of 2-methoxyestrone (2-MeO-E1) and 16α-hydroxyestrone (16α-OH-E1) on the biochemical and protein levels of MCF-7 were further studied to compare the effects of metabolic sites and modes on estrogen effects. Hydroxylation of E1 at the C2 site weakened the estrogen effect, down-regulated the expression of the mammalian target of rapamycin (mTOR) and protein kinase B (Akt) pathway proteins, inhibited the proliferation of cancer cells, and enhanced anti-oxidative stress and anti-inflammation. Methoxylation at the C2 position also inhibited the expression of inflammatory and oxidative stress pathway proteins but did not greatly affect the estrogen effects. However, hydroxylation on C16 had no significant effect on the biological effects of estrogen. Therefore, the structural changes of estrogen on C2 are important reasons for the different physiological effects of estrogen and its metabolites. Thus, by regulating the gene Cytochrome P450 1B1(CYP1B1), which affects the hydroxylation metabolism of estrogen, and promoting the hydroxylation of estrone at the C2 position, the estrogen effect of estrone can be effectively reduced, thus reducing the harm its poses in food and the environment.

Investigation of diethylstilbestrol residue level in human urine samples by a specific monoclonal antibody.

Diethylstilbestrol (DES) is used as a kind of animal feed additive and affects people's health through the food chain. The purpose of this study is to detect the residue level of DES in 576 human urine samples directly. DES-BSA was used to immunize Balb/c mice. The monoclonal antibody was produced by hybridoma that was screened through cell fusion techniques. Finally, we developed the indirect competitive ELISA method to analyze 576 human urine samples from Zhejiang Province, China. The IC50 of this method was 3.33ng/mL. The LOD and LOQ were 0.16 and 0.54ng/mL. Linear range of the standard curve was from LOD to 12.50ng/mL. There was no cross-reactivity with two kinds of estrogens and two structural analogs with DES. Five hundred seventy-six urine samples were analyzed by the indirect competitive ELISA method, and the detection rate was 98.78%. The mean concentration and geometric mean were 4.70 and 3.50ng/mL. The indirect competitive ELISA method based on monoclonal antibody was sensitive and reliable for the detection of DES in human urine samples. The results warned us to pay more attention to human health and food safety.

Simultaneous Determination of Hexoestrol, Diethylstilbestrol, Estrone and 17-Beta-estradiol in Feed by Gas Chromatography-mass Spectrometry

A method was developed for the simultaneous determination of four kinds of estrogens (hexoestrol, diethylstilbestrol, estrone, and 17-beta-estradiol) in feed by gas chromatography-mass spectrometry (GC-MS). After the sample was extracted by ethyl ether and cleaned-up on HLB phase extraction column, four kinds of estrogens were derived and quantified in gas chromatography-mass spectrometry. The results showed that the linear detectable ranged from 2.5 ng · mL−1 to 250 ng · mL−1 for hexoestrol and from 5 ng · mL−1 to 500 ng · mL−1 for three other estrogens with the correlation coefficients (R2) were no less than 0.990. The recoveries were in the range of 76.34%–96.33% and the relative standard deviation was no more than 22.7%. The limits of quantitation (LOQ) for all analytics were between 10 ug · kg−1 and 20 ug · kg−1. The method was accurate and sensitive and could meet the actual requirements for the analyses of feed samples.

Hollow fiber membrane-coated functionalized polymeric ionic liquid capsules for direct analysis of estrogens in milk samples.

Protein removal process is always time-consuming for the analysis of milk samples. In this work, hollow fiber membrane-coated functionalized polymeric ionic liquid (HF-PIL) capsules were synthesized and used as solid-phase microextraction (SPME) sorbent for direct analysis of estrogens in milk samples. The functionalized PIL monolith sorbent was obtained by copolymerization between 1-(3-aminopropyl)-3-(4-vinylbenzyl)imidazolium 4-styrenesulfonate IL monomer and 1,6-di(3-vinylimidazolium) hexane bishexafluorophosphate IL-crosslinking agent. A group of four capsules were installed as SPME device, to determine four kinds of estrogens (estrone, diethylstilbestrol, hexestrol, and 17α-ethynylestradiol) in milk samples, coupled to high performance liquid chromatography. Extraction and desorption conditions were optimized to get satisfactory extraction efficiency. Good linearity was obtained in the range of 5-200 μg L(-1). The limits of detection were 1 μg L(-1) for diethylstilbestrol and 2 μg L(-1) for 17α-ethynylestradiol, estrone, and hexestrol. The present method was applied to analyze the model analytes in different milk samples. Relative recoveries were in the range of 85.5-112%. The HF-PIL SPME capsules showed satisfactory extraction efficiency and high resistance to sample matrix interference.

Simultaneous Detection of Nine Kinds of Estrogens in Water by Solid Phase Extraction Coupled with Gas Chromatography-Mass Spectrometry

Nine target compounds including estrone (E-1), 17 beta-estradiol (17 beta-E-2), estriol (E-3) 4-octylphenol(4-OP), 4-nonylphenol (4-NP), bisphenol A (BPA), diethylstilbestrol (DES), mestranol (EE3ME) and 17 alpha-ethinyl estradiol (17 alpha-EE2) were simultaneous detected by SPE-GC-MS. Extraction and derivatization conditions were optimized. The results showed that the average recoveries of the nine target estrogens extracted by Oasis HLB cartridges were higher than those by Satara cartridges, the optimal temperature of derivatization reaction was 75 degrees C and the optimal time of derivatization reaction was 90 min. The average recoveries of the nine target estrogens by Oasis HLB cartridges were 60.5% - 126.7%, and the relative standard deviations (RSD) were 0.8% - 11.1%, and the limits of detection (LOD) ranged from 1.08 ng/L to 8.60 ng/L. This method has been employed to detect the estrogens in environment samples from rivers.

Determination of 29 Kinds of Estrogens in Milk and Milk Products by Liquid Chromatography Tandem Mass Spectrometry

Determination of 29 Kinds of Estrogens in Milk and Milk Products by Liquid Chromatography Tandem Mass Spectrometry

Determination of 29 Kinds of Estrogens in Milk and Milk Products by Liquid Chromatography Tandem Mass Spectrometry

Determination of 29 Kinds of Estrogens in Milk and Milk Products by Liquid Chromatography Tandem Mass Spectrometry

Determination of estrogens in human urine by high-performance liquid chromatography/diode array detection with ultrasound-assisted cloud-point extraction

A novel and efficient analytical methodology is proposed for extracting and preconcentrating three kinds of estrogens (17β-estradiol (βE2), estrone (E1), and diethylstilbestrol (DES)) in human urine prior to high-performance liquid chromatography (HPLC) analysis. It is based on the induction of micellar organized medium by using a nonionic surfactant (Tergitol TMN-6) to extract the target estrogens. Ultrasound was applied to enhance the extraction efficiency. Parameters affecting the extraction of target analytes including the concentration of surfactant, temperature, extraction time, sample pH, ionic strength, and centrifuging time were investigated. Under the optimum conditions, the linear range of βE2, E1, and DES was from 5.0 to 1000ng/ml. All correlation coefficients of the calibration curves were higher than 0.997. The relative standard deviations (RSD, n=5) were 2.36–5.27% and the limits of detection (LOD) were 0.1, 0.2, and 0.1ng/ml for βE2, E1, and DES in human urine, respectively. The results indicated that the method was successfully applied for analyzing βE2, E1, and DES in human urine.

Development and Application of Dispersion Solid-Phase Extraction for Estrogens in Aquatic Animal Samples

A simple, fast, robust, sensitive, and specific method for the confirmation and quantification of four kinds of estrogens, including 17β-estradiol (E2), estriol (E3), 4-hydroxyestradiol (4-OHE2), and 2-methoxyestradiol (2-MeOE2), in fortified and incurred fish and shrimp flesh samples was developed. The method used simple extraction of a sample with acetonitrile, dispersive solid-phase extraction (dispersive SPE) cleanup, and high-performance liquid chromatography (HPLC) coupled with a fluorescence detector for confirmation and quantitation. Compared with conventional SPE cleanup, dispersive SPE greatly simplified and accelerated sample cleanup and was less time-consuming. Average recoveries of fortified samples were more than 80% for all estrogens except 4-OHE2, which had an average recovery of 60%. The results showed good repeatability that the variation coefficients of the instrument precision and the method were less than 8% and 13%, respectively. The relative standard deviation (RSD) of intraday repeatability tests was generally less than 12%.This method was able to demonstrate quantitative recoveries and provide confirmatory data for unambiguous analyte identification.

Hormone replacement Up-to-date. Menopause in women and hormone replacement therapy (HRT). Indications for HRT in postmenopausal women

It has been generally accepted that it is quite sensible to administer hormone replacement therapy (HRT) in women to compensate for the estrogen deficiency that occurs as they approach menopause and that, given its broad-ranging efficacy, it has a huge benefit to offer to these women. However, it has been demonstrated in 2002 in the NIH-initiated Women's Health Initiative (WHI) trial that HRT may be associated with risk depending on whom it is used for. Thus, HRT has had a high profile in recent years. While the findings from the WHI trial are compelling in their own right, on closer examination, it has become clear that they do not necessarily translate into local practice here in Japan. Again, a further examination of HRT as a treatment modality reveals that the benefit and risk profile of HRT varies greatly depending on the timing for its initiation,the kind of estrogen or progesterone used and their route of administration and dosing. Therefore, in deciding to go for HRT, it needs to be weighed carefully for its benefit and risk in individual patients, and informed consent obtained for its administration, in view of the risk associated with its use versus its enormous benefit.

Characteristics of estrogen decomposition by ozonation

Since the natural estrogens 17 beta-estradiol (E2) and estron (E1), and the synthetic estrogen 17 alpha-ethynyl estradiol (EE2) have strong endocrine disrupting effects and the tendency to persist in effluent from wastewater treatment plants, effective measures are needed to remove them from wastewater. In this research, to gain an understanding of the characteristics of estrogen decomposition by ozonation, experiments were conducted using effluent from an actual wastewater treatment plant. In this experiment, estrogen was added to effluent at a concentration of 200 ng/l and 20 ng/l before the ozonation experiments. The results showed 90% or more of estrogen concentration and estrogenic activity of E2, El and EE2 to be removed at an ozone dose of 1 mg/l. At an ozone dose of 3 mg/l, the estrogen concentration and estrogenic activity of E2, El and EE2 in the treated water fell below the detection limit. The removal rate was not influenced by the kind of estrogen. No generation of byproducts with estrogenic activity was observed. The authors conclude that estrogen in secondary treated wastewater can be almost entirely removed at the practical ozone dose rate applied for the purpose of disinfection, which is up to about 5 mg/l.

Determination of estrogens in water by HPLC–UV using cloud point extraction

A method based on cloud point extraction was developed to determine four kinds of estrogens: estriol (E3), estradiol (E2), estrone (E1), and progesterone (P) in water by high performance liquid chromatography separation and ultraviolet detection (HPLC–UV). The non-ionic surfactant Triton X-114 was chosen as extractant solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na 2SO 4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, preconcentration factors of 99 for E3, 73 for E2, 152 for E1 and 86 for P were obtained for 10 mL water sample. The detection of limitation was 0.23 ng mL −1 for E3, 0.32 ng mL −1 for E2, 0.25 ng mL −1 for E1 and 5.0 ng mL −1 for P. The proposed method was successfully applied to the determination of trace amount of estrogens in wastewater treatment plant (WWTP) effluent water and exposure water with 10 ng mL −1 E2 for toxicological study in our lab. For the case of WWTP effluent water samples, no estrogen was found. The accuracy of the proposed method was tested by recovery measurements of spiked samples and good recoveries of 81.2–99.5% were obtained.

Women's heart problems are poorly understood.

Why and when women develop heart disease is both poorly understood and studied, said experts at the 21st Congress of the European Society of Cardiology, held in Barcelona. “Men and women are similar with regard to risk factors,” said John Martin, MD, of the University of London Cardiology Group. These similar heart disease risk factors include high blood pressure, high cholesterol, smoking, and age, said Dr Martin. Yet, he said, women with diabetes often have a higher risk of heart disease than men with diabetes. Women are also more likely to die of a first heart attack than men. As with men, death rates from heart disease in women vary from country to country. Heart disease death rates for women are lowest in Spain and highest in Scotland, he said. Again, as with men, this variation in rates is not well-understood. Even more puzzling are the variations in death rates, particularly in the acute phase just after a heart attack, when the patient is hospitalized. In a recent study in the New England Journal of …

Estrogens, progestins, and coronary artery reactivity in atherosclerotic monkeys

It has been known for many years that sex hormones modulate vasodilator responses of arteries supplying the uterus with blood. Recently, it has been shown that sex hormones such as estrogen modulate vasomotor responses of other arteries, including coronary arteries. It is thought that modulation of vasodilator and constrictor responses of coronary arteries may be one mechanism by which estrogen affects the risk of coronary heart disease. Although several studies have examined the effects (and potential mechanisms) of estrogen on vasodilator responses of nonatherosclerotic arteries, few have focused on estrogen's effects on atherosclerotic coronary arteries. In studies of ovariectomized atherosclerotic female cynomolgus monkeys, both long-term (2 years) and short-term (20 min) estradiol treatment augments dilator responses to acetylcholine, but not nitroglycerin. Presumably, this indicates an effect of estradiol on endothelium-mediated dilator responses of coronary arteries. Addition of the progestin medroxyprogesterone acetate diminishes the beneficial effect of conjugated equine estrogens on these dilator responses. This is significant because a progestin is usually added to estrogen replacement to reduce the risk of endometrial and breast cancer associated with unopposed estrogen therapy. However, it would seem that not all progestins act similarly on vascular reactivity. Studies in monkeys indicate that addition of progesterone or the progestin medroxyprogesterone acetate does not diminish the beneficial effects of estrogen on coronary dilator responses. Thus it would appear that different estrogen/progestin combinations may affect vascular reactivity in different manners, There is also an effort being made to examine the potential of different kinds of estrogens on cardiovascular risk. Studies in monkeys indicate that one of the estrogens found in conjugated equine estrogens (17 alpha-dihydroequilenin) has estrogen effects on vascular reactivity without having detrimental effects on uterine pathology. The isoflavones “plant estrogens” found in soy protein also have estrogenic effects on vascular reactivity and inhibition.

Changes of estrogens in milk of thoroughbred mares during foal estrus.

Levels of three kinds of estrogens, estrone, estradiol-17β and estriol, in milk from 5 Thoroughbred mares during foal estrus were measured by radioimmunoassay. Estradiol-17β and estriol levels in milk have no relevant importance in predicting con-ceptionable estrus. Only estrone concentration in milk showed a relation to the con-ceptionable estrus cycle in thoroughbred mares. This is probably the first report that deals with estrone concentration in milk during foal estrus and the measurement of estrone could be a reliable guide to know the estrus to be capable of conception in postpartum mares.

Desensitization of the chick oviduct to estrogen: mediation at different levels of gene expression.

We have investigated the effects of changing the dosage or kind of estrogen administered to immature chicks on the synthesis of two egg white proteins, ovalbumin and conalbumin, and the accumulation of their mRNAs. The results suggest that the oviduct can become desensitized to estrogen. Ovalbumin accounted for 25% of oviduct protein synthesis in chicks treated with low dose of diethylstilbestrol (DES; 0.5 mg/day) for 14 days. Within several days after the dosage of estrogen had been increased 10-fold, ovalbumin synthesis fell to undetectable levels. The synthesis of conalbumin also became undetectable when the dosage of estrogen was increased. Throughout the above experiment both ovalbumin and conalbumin mRNA activity, as measured by cell-free translation, remained elevated. This implies that expression of the ovalbumin and conalbumin genes may be regulated at the level of translation. In a separate experiment, ovalbumin and conalbumin synthesis also decreased when chicks primed with DES pellets were given an increased dosage of estrogen. Ovalbumin synthesis fluctuated, but overall decreased from 25% of oviduct protein synthesis after priming with DES pellets to 16% of oviduct protein synthesis after 7-12 days of injections of estradiol benzoate (1 mg/day). At the same time, conalbumin synthesis decreased from 10% to 6% of oviduct protein synthesis. In contrast with the previous results, changes in ovalbumin and conalbumin mRNA activity paralleled changes in ovalbumin and conalbumin synthesis. Thus, not only can the oviduct become desensitized to estrogen, desensitization can be mediated at different levels of gene expression.