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The Science of the Total Environment Jul 2020Our recent study revealed some early molecular and cellular events in which 17β-estradiol (E2) disrupted testis differentiation and resulted in feminization in Xenopus...
Transcriptional changes caused by estrogenic endocrine disrupting chemicals in gonad-mesonephros complexes of genetic male Xenopus laevis: Multiple biomarkers for early detection of testis differentiation disruption.
Our recent study revealed some early molecular and cellular events in which 17β-estradiol (E2) disrupted testis differentiation and resulted in feminization in Xenopus laevis (the African clawed frog), an ideal species for studying reproductive endocrine disruption by estrogenic endocrine disrupting chemicals (EDCs). On this basis, we aimed to develop multiple biomarkers for early detection of testis differentiation disruption by estrogenic EDCs in X. laevis. Tadpoles at stage 45/46 were exposed to four known estrogenic EDCs with different estrogenic activities, including E2, diethylstilbestrol (DES), mestranol (MES) and 4-n-nonyphenol (NP). At stage 53, gonadal morphological and histological changes as well as altered sex-dimorphic gene expression in gonad-mesonephros complexes (GMCs) showed that these estrogenic EDCs disrupted testis differentiation and caused feminization to different degrees. Then we measured transcriptional changes of 48 candidate genes, which are believed to be associated with E2-induced testis differentiation alterations, in GMCs at stage 50. As a result, 19 genes were found to be transcriptionally altered by all test chemicals and proposed as promising biomarkers for early detection of testis differentiation disruption by estrogenic EDCs. Finally, all biomarker responses were integrated as integrated biomarker response (IBR) index to characterize testis differentiation disruption by these estrogenic EDCs in X. laevis. Compared with the methods used in previous studies, the multiple biomarker test using X. laevis at early developmental stages largely shortens the exposure duration, thereby achieving the goal of rapid detection. Certainly, the biomarker test needs further validations in the future study.
Topics: Animals; Biomarkers; Endocrine Disruptors; Gonads; Male; Mesonephros; Testis; Xenopus laevis
PubMed: 32335401
DOI: 10.1016/j.scitotenv.2020.138522 -
Molecules (Basel, Switzerland) Feb 2019Microwave-assisted syntheses of novel ring d-condensed 2-pyrazolines in the estrone series were efficiently carried out from steroidal ,-enones and hydrazine...
Microwave-assisted syntheses of novel ring d-condensed 2-pyrazolines in the estrone series were efficiently carried out from steroidal ,-enones and hydrazine derivatives. The ring-closure reaction of 16-benzylidene estrone 3-methyl ether with hydrazine in acetic acid resulted in a 2:1 diastereomeric mixture of two 16,17- fused pyrazolines, which is contrary to the former literature data for both stereoselectivity and product structure. However, the cyclization reactions of a mestranol-derived unsaturated ketone with different arylhydrazines in acidic ethanol furnished the heterocyclic products in good to excellent yields independently of the substituents present on the aromatic ring of the reagents applied. The MW conditions also permitted the ring-closure reaction with -nitrophenylhydrazine which is unfavorable under conventional heating. Moreover, the transformations led to the heterocyclic compounds stereoselectively with a 16,17- ring junction without being susceptible to spontaneous and promoted oxidation to pyrazoles.
Topics: Cyclization; Estrone; Microwaves; Models, Molecular; Molecular Structure; Pyrazoles; Stereoisomerism
PubMed: 30720767
DOI: 10.3390/molecules24030569 -
Anti-cancer Agents in Medicinal... 2018RM-133 belongs to a new family of aminosteroid derivatives demonstrating interesting anticancer properties, as confirmed in vivo in four mouse cancer xenograft models....
Parallel Solid-Phase Synthesis using a New Diethylsilylacetylenic Linker and Leading to Mestranol Derivatives with Potent Antiproliferative Activities on Multiple Cancer Cell Lines.
BACKGROUND
RM-133 belongs to a new family of aminosteroid derivatives demonstrating interesting anticancer properties, as confirmed in vivo in four mouse cancer xenograft models. However, the metabolic stability of RM-133 needs to be improved. After investigation, the replacement of its androstane scaffold by a more stable estrane scaffold led to the development of the mestranol derivative RM-581.
METHODS
Using solid-phase strategy involving five steps, we quickly synthesized a series of RM-581 analogs using the recently-developed diethylsilylacetylenic linker. To establish structure-activity relationships, we then investigated their antiproliferative potency on a panel of cancer cell lines from various cancers (breast, prostate, ovarian and pancreatic).
RESULTS
Some of the mestranol derivatives have shown in vitro anticancer activities that are close to, or better than, those observed for RM-581. Compound 23, a mestranol derivative having a ((3,5-dimethylbenzoyl)- L-prolyl)piperazine side chain at position C2, was found to be active as an antiproliferative agent (IC50 = 0.38 ± 0.34 to 3.17 ± 0.10 µM) and to be twice as active as RM-581 on LNCaP, PC-3, MCF-7, PANC-1 and OVCAR-3 cancer cells (IC50 = 0.56 ± 0.30, 0.89 ± 0.63, 1.36 ± 0.31, 2.47 ± 0.91 and 3.17 ± 0.10 µM, respectively).
CONCLUSION
Easily synthesized in good yields by both solid-phase organic synthesis and classic solution-phase chemistry, promising compound 23 could be used as an antiproliferative agent on a variety of cancers, notably pancreatic and ovarian cancers, both having very bad prognoses.
Topics: Acetylene; Antineoplastic Agents; Cell Proliferation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Mestranol; Molecular Conformation; Solid-Phase Synthesis Techniques; Structure-Activity Relationship; Tumor Cells, Cultured
PubMed: 29521249
DOI: 10.2174/1871520618666180307130158 -
Pharmacology 2015Mestranol is a widely used estrogen, which is converted into its active metabolite ethinyl estradiol by cytochrome P450 (CYP) 2C9. To comprehensively examine the...
BACKGROUND
Mestranol is a widely used estrogen, which is converted into its active metabolite ethinyl estradiol by cytochrome P450 (CYP) 2C9. To comprehensively examine the enzymatic activity of reported CYP2C9 variants in Chinese individuals in response to mestranol, wild-type CYP2C9*1 and 35 allelic variants were highly expressed in Sf21 insect cell microsomes and used for the detection of their enzymatic values in vitro. These results showed that the majority of tested variants exhibited decreased clearance values compared to wild type, except for CYP2C9*40 and *36.
METHOD
Insect microsomes expressing the 36 CYP2C9 variants were incubated with 0.25-8 μmol/l mestranol for 30 min at 37°C. Then, the production of the metabolite of mestranol, ethinyl estradiol, was analyzed using high-performance liquid chromatography.
RESULTS
Most CYP-catalyzed reactions were sufficiently described by classical Michaelis-Menten kinetic parameters (e.g., Km and Vmax), while 9 variants exhibited atypical or non-Michaelis-Menten kinetic values, which were largely due to the self-inhibitory effect in response to mestranol.
CONCLUSION
This is the first report of these rare alleles for mestranol metabolism, which provides fundamental data for further clinical studies on CYP2C9 alleles for mestranol metabolism.
Topics: Animals; Asian People; Cytochrome P-450 CYP2C9; Estrogens; Humans; Insecta; Mestranol; Microsomes; Polymorphism, Genetic
PubMed: 25924705
DOI: 10.1159/000381189 -
Organic Letters Sep 2016An efficient and transition-metal-free method is presented to access tertiary alkyl aryl ethers by arylation of tertiary alcohols with ortho-substituted diaryliodonium...
An efficient and transition-metal-free method is presented to access tertiary alkyl aryl ethers by arylation of tertiary alcohols with ortho-substituted diaryliodonium salts. The scope covers cyclic and acyclic aliphatic, benzylic, allylic, and propargylic tertiary alcohols as well as primary and secondary fluorinated alcohols. The methodology gives access to alkyl aryl ethers of previously unprecedented steric congestion. Furthermore, the versatility of the developed procedure was demonstrated by arylation of the pro-drug mestranol.
PubMed: 27586361
DOI: 10.1021/acs.orglett.6b01975 -
Journal of Chromatography. A Oct 2014In this paper, development and optimization of new LC-MS method for determination of twenty selected hormones, human/animal and plant sterols in river sediments were...
In this paper, development and optimization of new LC-MS method for determination of twenty selected hormones, human/animal and plant sterols in river sediments were described. Sediment samples were prepared using ultrasonic extraction and clean up with silica gel/anhydrous sodium sulphate cartridge. Extracts were analyzed by liquid chromatography-linear ion trap-tandem mass spectrometry, with atmospheric pressure chemical ionization. The optimized extraction parameters were extraction solvent (methanol), weight of the sediment (2 g) and time of ultrasonic extraction (3× 10 min). Successful chromatographic separation of hormones (estriol and estrone, 17α- and 17β-estradiol) and four human/animal sterols (epicoprostanol, coprostanol, α-cholestanol and β-cholestanol) that have identical fragmentation reactions was achieved. The developed and optimized method provided high recoveries (73-118%), low limits of detection (0.8-18 ng g(-1)) and quantification (2.5-60 ng g(-1)) with the RSDs generally lower than 20%. Applicability of the developed method was confirmed by analysis of six river sediment samples. A widespread occurrence of human/animal and plant sterols was found. The only detected hormone was mestranol in just one sediment sample.
Topics: Chromatography, Liquid; Geologic Sediments; Hormones; Rivers; Spectrometry, Mass, Electrospray Ionization; Sterols; Tandem Mass Spectrometry; Water Pollutants, Chemical
PubMed: 25182857
DOI: 10.1016/j.chroma.2014.08.061 -
Ecotoxicology and Environmental Safety Oct 2017This study reports on the potential status of 17α-ethinylestradiol (EE2) and mestranol (MeEE2) residues in aquatic environments in New South Wales (NSW), Australia,...
A survey of 17α-ethinylestradiol and mestranol residues in Hawkesbury River, Australia, using a highly specific enzyme-linked immunosorbent assay (ELISA) demonstrates the levels of potential biological significance.
This study reports on the potential status of 17α-ethinylestradiol (EE2) and mestranol (MeEE2) residues in aquatic environments in New South Wales (NSW), Australia, based on the analysis by a specific ELISA we developed. Polyclonal antibodies were raised against the EE2 hapten with a linker attached at the C3-position to direct the antibody binding towards the ring D of EE2/MeEE2. Using this approach, an ELISA highly specific to EE2 and MeEE2 was successfully developed, showing less than 3.1% cross-reactivity (% CR) with other major steroidal sex hormones and their derivatives. The assay performed with the limit of detection (LOD) of 0.04 ± 0.01µg/L for both EE2 and MeEE2, and the limit of quantitation (LOQ) of 0.05 ± 0.01ng/L when it was coupled with the SM2-Biobeads solid phase extraction. Prior to conducting the survey study, it was validated against the gas chromatography-mass spectrophotometry (GC-MS) method, which showed high correlation with R of 0.934. Fresh surface water samples collected at different sites along Hawkesbury River in New South Wales (NSW) were analyzed for the EE2/ MeEE2 residues using the developed ELISA. The EE2/MeEE2 levels were found to range between 4.1 and 8.3ng/L in Emigrant Creek, NSW, where the primary activity was macadamia plantation, and higher levels between 15 and 29ng/L in South Creek, NSW, Greater Western Sydney at sites upstream and downstream of the municipal sewage treatment plants.
Topics: Animals; Antibodies, Monoclonal; Endocrine Disruptors; Enzyme-Linked Immunosorbent Assay; Ethinyl Estradiol; Limit of Detection; Mestranol; New South Wales; Rabbits; Rivers; Solid Phase Extraction; Surveys and Questionnaires; Water Pollutants, Chemical
PubMed: 28688361
DOI: 10.1016/j.ecoenv.2017.06.077 -
Cancer Causes & Control : CCC May 2017Oral contraceptives (OCs) have been consistently associated with a reduced ovarian cancer risk; however, most previous studies included women in older birth cohorts...
PURPOSE
Oral contraceptives (OCs) have been consistently associated with a reduced ovarian cancer risk; however, most previous studies included women in older birth cohorts using high-dose OC formulations. We assessed OC use, including type and dose, and ovarian cancer risk among women born between 1947 and 1964 using more recent formulations.
METHODS
We included 110,929 Nurses' Health Study II participants. Women reported duration of OC use and brands used from age 13 to baseline (1989) and every 2 years thereafter through 2009. We categorized brands by estrogen and progestin type, dose, and potency, and used Cox proportional hazards models, adjusted for age, calendar time, reproductive factors, and body mass index, to assess associations with ovarian cancer.
RESULTS
Over 2,178,679 person-years of follow-up, we confirmed 281 cases. At baseline, 83% of participants reported ever using OCs. Compared to never use, we observed an increased risk of ovarian cancer with ≤6 months of OC use (HR 1.82; 95% CI 1.13-2.93) but a non-significant 57% (95% CI 0.18-1.03) decreased risk with ≥15 years of OC use. The increased risk among short-term users (≤1 year) was restricted to OCs containing mestranol (HR 1.83; 95% CI 1.16-2.88) and first-generation progestin (HR 1.72; 95% CI 1.11-2.65).
CONCLUSION
The associations between OCs and ovarian cancer observed for this younger birth cohort differ substantially from the results of previous cohort studies, possibly reflecting changes in OC formulations and use patterns over time, although these results could be due to chance. Additional studies should evaluate newer OC formulations and ovarian cancer risk.
Topics: Adolescent; Adult; Contraceptives, Oral; Female; Health Surveys; Humans; Incidence; Middle Aged; Ovarian Neoplasms; Prospective Studies; United States; Women's Health; Young Adult
PubMed: 28290016
DOI: 10.1007/s10552-017-0876-0 -
Journal of Chromatography. A Aug 2014Membrane-assisted solvent extraction (MASE) coupled to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) was studied for the determination of a...
Matrix effect during the membrane-assisted solvent extraction coupled to liquid chromatography tandem mass spectrometry for the determination of a variety of endocrine disrupting compounds in wastewater.
Membrane-assisted solvent extraction (MASE) coupled to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) was studied for the determination of a variety of emerging and priority compounds in wastewater. Among the target analytes studied certain hormones (estrone (E1), 17β-estradiol (E2), androsterone (ADT), 17α-ethynyl estradiol (EE2), diethylstilbestrol (DES), equilin (EQ), testosterone (TT), mestranol (MeEE2), 19-norethisterone (NT), progesterone (PG) and equilenin (EQN)), alkylphenols (APs) (4-tert-octylphenol (4tOP), nonylphenol technical mixture (NPs) and 4n-octylphenol (4nOP)) and BPA were included. The work was primarily focused in the LC-MS/MS detection step, both in terms of variable optimization and with respect to the matrix effect study. Both, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) were assessed both in the negative and positive mode, including the optimization of MS/MS operating conditions. The best results were obtained, in most of the cases, for ESI using 0.05% ammonium hydroxide as buffer solution in the mobile phase, composed with methanol and water. Under optimum detection conditions, matrix effect during the detection step was thoroughly studied. Dilution, correction with deuterated analogues and clean-up of the extracts were evaluated for matrix effect correction. Clean-up with Florisil together with correction with deuterated analogues provided the most satisfactory results, with apparent recoveries in the 57-136% range and method detection limits in the low ngL(-1) level for most of the analytes. For further validation of the method, two separated extraction procedures, the above mentioned MASE, and conventional solid phase extraction (SPE) were compared during the analysis of real samples and comparable results were successfully obtained for E1, E2, EE2, DES, NT, TT, EQ, PG, BPA, ADT, 4nOP, 4tOP, NPs and EQN.
Topics: Androstanes; Benzhydryl Compounds; Chromatography, High Pressure Liquid; Diethylstilbestrol; Endocrine Disruptors; Estrenes; Hydrogen-Ion Concentration; Limit of Detection; Liquid-Liquid Extraction; Phenols; Solid Phase Extraction; Solvents; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Wastewater; Water Pollutants, Chemical
PubMed: 25001332
DOI: 10.1016/j.chroma.2014.06.051 -
Talanta May 2015In the present work, the development of a novel analytical approach which combines a miniaturized bar adsorptive microextraction device with a micro-liquid desorption in...
In the present work, the development of a novel analytical approach which combines a miniaturized bar adsorptive microextraction device with a micro-liquid desorption in one single step, followed by high performance liquid chromatography with diode array detection (BAµE-µLD/HPLC-DAD), is proposed for the determination of trace levels of nine steroid hormones (estriol, 17ß-estradiol, 17α-estradiol, 19-northisterone, 17α-ethynylestradiol, estrone, D-(-)-norgestrel, progesterone and mestranol) in environmental and biological matrices. From the comparison of ten different coating phases (five polymeric and five activated carbon sorbents), the modified pyrrolidone polymer (P2) showed the best compromise between selectivity and efficiency. Assays performed through BAµE(P2, 1.3mg)-µLD(100µL)/HPLC-DAD on 25mL of ultrapure water samples spiked at the 6.0μg/L level, yielded recoveries ranging from 93±9% to 101±8%, under optimized experimental conditions. The analytical performance showed convenient detection (50.0-100.0ng/L) and quantification limits (165.0-330.0ng/L), as well as good linear dynamic ranges (0.2-24.0µg/L) with remarkable determination coefficients (r(2)>0.9968). Excellent repeatability were also achieved through intraday (RSD<14%) and interday (RSD<12%) experiments. The application of the proposed analytical approach on environmental water and urine samples, using the standard addition methodology (SAM), revealed good linearity and sensitivity at trace level, with the detection of some of the target compounds. In short, the miniaturization of the analytical device for microextraction combined with the minimization of the solvent volume for back-extraction in one single step demonstrated remarkable performance, increasing the enrichment factor, being simultaneously more easier to implement and environment friendly.
Topics: Adsorption; Carbon; Chemical Fractionation; Chromatography, High Pressure Liquid; Gonadal Steroid Hormones; Pyrrolidinones
PubMed: 25702996
DOI: 10.1016/j.talanta.2014.11.013