Diethylstilbestrol Research Articles

Oestrogenic Endocrine Disruptors in the Placenta and the Fetus.

Endocrine disrupting chemicals (EDCs) are exogenous substances that interfere with the stability and regulation of the endocrine system of the body or its offspring. These substances are generally stable in chemical properties, not easy to be biodegraded, and can be enriched in organisms. In the past half century, EDCs have gradually entered the food chain, and these substances have been frequently found in maternal blood. Perinatal maternal hormone levels are unstable and vulnerable to EDCs. Some EDCs can affect embryonic development through the blood-fetal barrier and cause damage to the neuroendocrine system, liver function, and genital development. Some also effect cross-generational inheritance through epigenetic mechanisms. This article mainly elaborates the mechanism and detection methods of estrogenic endocrine disruptors, such as bisphenol A (BPA), organochlorine pesticides (OCPs), diethylstilbestrol (DES) and phthalates (PAEs), and their effects on placenta and fetal health in order to raise concerns about the proper use of products containing EDCs during pregnancy and provide a reference for human health.

Estrogen receptor alpha (ER\u03b1)\u2013mediated coregulator binding and gene expression discriminates the toxic ER\u03b1 agonist diethylstilbestrol (DES) from the endogenous ER\u03b1 agonist 17\u03b2-estradiol (E2)

Diethylstilbestrol (DES) is a synthetic estrogen and proven human teratogen and carcinogen reported to act via the estrogen receptor α (ERα). Since the endogenous ERα ligand 17β-estradiol (E2) does not show these adverse effects to a similar extent, we hypothesized that DES’ interaction with the ERα differs from that of E2. The current study aimed to investigate possible differences between DES and E2 using in vitro assays that detect ERα-mediated effects, including ERα-mediated reporter gene expression, ERα-mediated breast cancer cell (T47D) proliferation and ERα-coregulator interactions and gene expression in T47D cells. Results obtained indicate that DES and E2 activate ERα-mediated reporter gene transcription and T47D cell proliferation in a similar way. However, significant differences between DES- and E2-induced binding of the ERα to 15 coregulator motifs and in transcriptomic signatures obtained in the T47D cells were observed. It is concluded that differences observed in binding of the ERα with several co-repressor motifs, in downregulation of genes involved in histone deacetylation and DNA methylation and in upregulation of CYP26A1 and CYP26B1 contribute to the differential effects reported for DES and E2.

Sandwich magnetically imprinted immunosensor for electrochemiluminescence ultrasensing diethylstilbestrol based on enhanced luminescence of Ru@SiO2 by CdTe@ZnS quantum dots

A molecularly imprinted magnetic sensor with electroluminescent tags (MIP-ECL sensor) was developed for ultrasensing diethylstilbestrol (DES). A strategy is exploited to enhance ECL emission of the [Ru(bpy)3]2 +-tripropyl amine (TPrA) system by CdTe@ZnS quantum-dots (QDs) through energy transfer. Magnetically molecularly imprinted nanoparticles (MMIPs NPs) based on Fe3O4@SiO2 carriers are artificial, easily reproducible, and could replace easily inactivated first antibodies for capturing more DES molecules. Functionalized bio-conjugates of single antibody-CdTe@ZnS (Ab-CdTe@ZnS) are for the first time loaded on signal labels of Ru(bpy)32 +-doped silica nanocomposites (Ru@SiO2) for signal amplification. The final bio-conjugated signal probes are denoted as Ab-DES/CdTe@ZnS–Ru@SiO2. MMIPs beads that have captured antigens are bio-conjugated with antibody-labeled luminescent probes by specific immunoreactive reaction, and then the luminescent immunocomplex generates ECL signal on the magnetic electrode. The logarithm of ECL intensities depend linearly on the logarithm of DES concentrations in the range from 4.8 × 10− 4 to 36.0 nM with a detection limit of 0.025 pM. This novel assay is much more sensitive than other MIP sensors, and achieves lower cost and more enhanced stability than other immunosensors. The sensor is significantly potential and has been applied to DES detection in actual environment.

Diethylstilbestrol exposure disrupts mouse oocyte meiotic maturation in vitro through affecting spindle assembly and chromosome alignment

An adverse tendency induced by the environmental estrogens in female reproductive health is one serious problem worldwide. Diethylstilbestrol (DES), as a synthetic estrogen, is still used as an animal growth stimulant in terrestrial livestock and aquaculture illegally. It has been reported to negatively affect ovarian function and oogenesis. Nevertheless, the mechanism and toxicity of DES on oocyte meiotic maturation are largely unknown. Herein, we found that DES (40 μM) intervened in mouse oocyte maturation and first polar body extrusion (PBE) was decreased in vitro. Cell cycle analysis showed meiotic process was disturbed with oocytes arrested at metaphase I (MI) stage after DES exposure. Further study showed that DES exposure disrupted the spindle assembly and chromosome alignment, which then continuously provoke the spindle assemble checkpoint (SAC). We also observed that the acetylation levels of α-tubulin were dramatically increased in DES-treated oocytes. In addition, the dynamics of actin were also affected. Moreover, the distribution patterns of estrogen receptor α (ERα) were altered in DES-treated oocyte, as indicated by the significant signals accumulation in the spindle area. However, ERα inhibitor failed to rescue the defects of oocyte maturation caused by DES. Of note, the same phenomenon was observed in estrogen-treated oocytes. Collectively, we showed that DES exposure lead to the oocyte meiotic failure via impairing the spindle assembly and chromosome alignment. Our research is helpful to understand how environmental estrogen affects female germ cells and contribute to design the potential therapies to preserve fertility especially for occupational exposure.

Gender Identity and Sexual Orientation Identity in Women and Men Prenatally Exposed to Diethylstilbestrol

We assessed the associations of prenatal diethylstilbestrol (DES) exposure, a potent estrogen, with sexual orientation and gender identity in 3306 women and 1848 men who participated in a study of prenatal DES exposure. Odds ratios (OR) and 95% confidence intervals (CI) were derived from logistic regression models adjusted for birth year, study cohort, and education. Among women, the OR for DES in relation to reporting sexual orientation identity as nonheterosexual was 0.61 (95% CI 0.40–0.92) primarily due to a strong inverse association with a lesbian identity (OR 0.44, 95% CI 0.25–0.76). Among men, the OR for DES in relation to reporting a nonheterosexual sexual orientation identity was 1.4 (95% CI 0.82–2.4), and ORs were similar for having a gay identity (1.4, 95% CI 0.72–2.85) and bisexual identity (1.4, 95% CI 0.57–3.5). Only five individuals reported a gender identity not conforming to that assigned at birth, preventing meaningful analysis. Women who were prenatally exposed to DES were less likely to have a lesbian or bisexual orientation, while DES-exposed men were somewhat more likely to report being gay or bisexual, but estimates were imprecise.

Avian eggshell thinning caused by transovarian exposure to o,p'-DDT: changes in histology and calcium-binding protein production in the oviduct uterus.

Reproductive disorders in birds are the most characteristic effects of DDT contamination of wildlife. Experimental exposure of avian eggs to the estrogenic substance o,p'-DDT causes abnormal development of the reproductive tract (shortening of the left oviduct and aberrant development of the right oviduct) and eggshell thinning in mature birds, but it is still not known how eggshell thinning occurs in the abnormal oviduct. To fill this information gap, we examined the histology of the uterine part of the oviduct in Japanese quail treated in ovo with o,p'-DDT or a synthetic estrogen, diethylstilbestrol (DES), and we performed immunohistochemical staining for the calcium-binding proteins CALB1, SPP1, and TRPV6. Both o,p'-DDT-treated and DES-treated quail had few, and scattered, gland cells in the left uterus, unlike vehicle controls, in which gland cells tightly occupied the lamina propria. The aberrantly developed right uterus retained all the components of the normal left uterus, but in immature form. Immunostaining for CALB1, SPP1, and TRPV6 was greatly reduced by both o,p'-DDT and DES; SPP1 and TRPV6 immunostaining patterns, in particular, differed distinctly from those in the controls. These findings suggest that CALB1, SPP1, and TRPV6 are molecular factors, decreased production of which is responsible for eggshell thinning. Our findings also could contribute to understanding of the eggshell formation mechanism in birds.

Clear Cell Carcinoma of Cervix

Clear cell carcinoma of cervix is a rare tumor, accounting for about 4% of cases of cervical adenocarcinoma. It commonly occurs in young women whose mothers had been exposed to diethylstilbestrol (DES). We are reporting a case of clear cell carcinoma of cervix in a 58 year old postmenopausal woman with no history of intrauterine exposure of DES.

Novel PEP-PAN@PSF rods extraction of EDCs in environmental water, sediment, and fish homogenate followed by pre-column derivatization and UHPLC-MS/MS detection

In the study, novel polysulfone hollow fiber membrane (PSF) supported polar enhanced phase (PEP) particles-polyacrylonitrile (PAN) polymer thin-film rods (PEP-PAN@PSF rods) were developed for the extraction of five steroidal endocrine disrupting chemicals (EDCs) (estrone (E1), estradiol (E2), estriol (E3), ethinyloestradiol (EE2), 2-methoxyestradiol (2ME2)) and four phenolic EDCs (bisphenol A (BPA), hexestrol (HEX), diethylstilbestrol (DES), dienestrol (DE)) in environmental water, sediment, and fish muscle homogenates, followed by pre-column derivatization and ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The traditional preparation method for thin-film rods was improved by introducing a supporting membrane PSF between the external thin-film coating and the internal bare rod, avoiding the conventional pre-corrosion by strong acid/base. The commercial PEP prepared rods showed competitive capacity for both polar and nonpolar EDCs. In addition, pre-column derivatization with dansyl chloride (DNS-Cl) was adopted for the phenolic analytes prior to UHPLC-MS/MS detection, leading to a significant enhancement of sensitivity via analyzing the dansylated derivatives under positive electrospray ionization (ESI) mode instead of the analytes under negative ESI mode. The protocol was validated in four matrices including environmental water, sediment and two fish species. No matrix effects were observed in four matrices. The limits of detection (LODs) for the analytes were in the range of 0.002–0.072 μg L−1 for environmental water, 0.032–0.734 ng g−1 for sediment, and 0.011–0.435 ng g−1 for two fish species, respectively. Appropriate linearity was observed for all the analytes with correlation coefficients (R2) above 0.997. The intra-day trueness of the approach at low, medium and high levels was in the range of 86.6–116.1% with relative standard deviations (RSDs) lower than 15.4%. And the inter-day trueness was in the range of 84.6–114.8% with RSDs lower than 16.3%. The proposed method was successfully applied for the analysis of nine EDCs in environmental water, sediment, and fish muscle homogenates.

Electrochemiluminescence solid-state imprinted sensor based on graphene/CdTe@ZnS quantum dots as luminescent probes for low-cost ultrasensing of diethylstilbestrol

A novel molecularly imprinted electrochemiluminescence (MIP-ECL) sensor was fabricated for diethylstilbestrol (DES), which exploited the strategy of specific identification by molecularly imprinted polymers (MIPs) instead of expensive biomolecules. Core-shell quantum-dots (QDs) of CdTe@ZnS were utilized to enhance ECL emission. The sensor was assembled as a solid-state electrode by immobilizing CdTe@ZnS/reduced-graphene oxide (r-GO) composite on a glassy carbon electrode (GCE) surface, and then being covered with MIPs film with specific cavities. The fabricated sensor (denoted as MIP/CdTe@ZnS/r-GO/GCE) was based on the obstruction of ECL signals by DES molecules enriched on MIP film. The ECL intensity of the QDs-K2S2O8 system was reduced when the DES molecules were selectively rebound onto the MIP film by molecularly imprinted solid phase extraction (MISPE). Accordingly, the logarithm of the quenched ECL intensity versus the logarithm of the DES concentration was in a good linear relationship over a wide range from 1.8 × 10− 3 to 25.0 nmol/L with the limit of detection (LOD) of 0.25 pmol/L (S/N = 3). The sensor also exhibits excellent selectivity with fast response and good accuracy. Lake water and milk samples were assayed by this sensor, and the recoveries ranging from 92.2%–108.3% were obtained.

Estrogens in municipal wastewater and receiving waters in the Beijing-Tianjin-Hebei region, China: Occurrence and risk assessment of mixtures

The potentially high release of estrogens to surface waters due to high population density and local livestock production in the Beijing-Tianjin-Hebei region may pose adverse effects on reproductive systems of aquatic organisms. This study found that total measured concentrations of estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2) and diethylstilbestrol (DES) were 468 ± 27 ng/L in treated wastewater and 219 ± 23 ng/L in river waters in this region. E2, E3 and EE2 were the predominant estrogens in river waters. The restriction of DES for human use should have been enforced, however concentrations of DES were relatively high compared to other studies. Haihe and Yongdingxin Rivers delivered approximately 1.8 tonnes of estrogens to the Bohai Bay annually. Concentrations of individual estrogens were significantly higher in river waters in the dry season, however, mass loadings were significantly higher in the wet season. The average E2-equivalent concentrations reached 1.2 ± 0.2 and 0.64 ± 0.08 μg-E2/L following long-term and short-term exposure estimates, respectively, in river waters with an EE2 contribution of over 90 %. This could give rise to high risks to fish. Estrogens in river waters largely derived from human excretion. Field studies on estrogenic effects on fish reproductive systems are required locally considering high estrogen contamination levels.

Epidemiological aspects of the outcomes from the treatment of endometriosis: Experience from two different geographical areas

The purpose of the present study was two-fold: First to review the epidemiological aspects of the experience on the surgical outcomes via laparotomy or laparoscopy, as regards endometriosis from two different academic institutions and, second, to illustrate potential differences in two different geographical areas, New Haven (US) and Greece. This retrospective study included 1,200 patients (15–80 years of age) treated via laparotomy or laparoscopy, at two different institutions, for endometriosis, between 1990 and 2017. Data were collected and analyzed from medical and pathological reports. The statistical methods used included the Student's t-test and χ2 test, as well as the Mann-Whitney U test. A total of 600 women from Yale University and 600 women from Greece participated in this study. Endometrioma was confirmed in 359 (29.9%) cases. Women were compatible in terms of the site of endometriomas. Left-sided cysts were observed (P<0.001) significantly more often compared with right-sided cysts in both groups. The two groups of patients had similar rates of endometriosis stages. A statistically significant positive association (P<0.001) was found for the co-existence of benign gynecological tumors (apart from endometrioma), endometriosis-associated ovarian cancer and for post-menopausal endometriosis in women with endometriosis from Greece. Moreover, similar results were observed as regards endometriosis following in utero exposure to diethylstilbestrol (DES), non-Hodgkin's lymphoma, endometriosis-associated Lyme disease, human immuno-deficiency virus (HIV), melanoma and endometriosis in adolescents, between the two groups. To conclude, the two populations exhibited similar results as regards the surgical outcomes of endometriosis laparoscopic or open surgery. Endometriosis represents a multifactorial entity that depends on complex interactions of hormonal, genetic, immunological and environmental factors. Gynecologists should be aware that there is an association between endometriosis and cancerous diseases. It is thus suggested that the presence of comorbidities in women with endometriosis.

SIX1 Regulates Aberrant Endometrial Epithelial Cell Differentiation and Cancer Latency Following Developmental Estrogenic Chemical Exposure.

Early-life exposure to estrogenic chemicals can increase cancer risk, likely by disrupting normal patterns of cellular differentiation. Female mice exposed neonatally to the synthetic estrogen diethylstilbestrol (DES) develop metaplastic and neoplastic uterine changes as adults. Abnormal endometrial glands express the oncofetal protein sine oculis homeobox 1 (SIX1) and contain cells with basal [cytokeratin (CK)14+/18-] and poorly differentiated features (CK14+/18+), strongly associating SIX1 with aberrant differentiation and cancer. Here, we tested whether SIX1 expression is necessary for abnormal endometrial differentiation and DES-induced carcinogenesis by using Pgr-cre to generate conditional knockout mice lacking uterine Six1 (Six1 d/d). Interestingly, corn oil (CO) vehicle-treated Six1 d/d mice develop focal endometrial glandular dysplasia and features of carcinoma in situ as compared with CO wild-type Six1 (Six1 +/+) mice. Furthermore, Six1 d/d mice neonatally exposed to DES had a 42% higher incidence of endometrial cancer relative to DES Six1 +/+ mice. Although DES Six1 d/d mice had >10-fold fewer CK14+/18- basal cells within the uterine horns as compared with DES Six1 +/+ mice, the appearance of CK14+/18+ cells remained a feature of neoplastic lesions. These findings suggest that SIX1 is required for normal endometrial epithelial differentiation, CK14+/18+ cells act as a cancer progenitor population, and SIX1 delays DES-induced endometrial carcinogenesis by promoting basal differentiation of CK14+/18+ cells. In human endometrial biopsies, 35% of malignancies showed CK14+/18+ expression, which positively correlated with tumor stage and grade and was not present in normal endometrium. IMPLICATIONS: Aberrant epithelial differentiation is a key feature in both the DES mouse model of endometrial cancer and human endometrial cancer. The association of CK14+/18+ cells with human endometrial cancer provides a novel cancer biomarker and could lead to new therapeutic strategies.

Copper-Based Metal–Organic Frameworks Loaded with Silver Nanoparticles as Electrochemical Immunosensors for Diethylstilbestrol

An ultrasensitive competitive electrochemical immunosensor for the quantitative detection of diethylstilbestrol (DES) was constructed by linear-sweep voltammetry. In this work, copper-based metal–o...

Isolation and Characterization of a Novel Diethylstilbestrol-Degrading Bacillus subtilis JF and Biochemical Degradation Metabolite Analysis.

Diethylstilbestrol (DES) can adversely affect the immune system of developing fetuses or even elicit toxic responses such as nerve toxicity and genotoxicity in human beings, thereby warranting methods to remove DES from the environments. The present study characterized a novel DES-degrading Bacillus subtilis JF and analyzed the degradation metabolites. The strain was collected at the China General Microbiological Culture Collection Center (Collection number: CGMCC 7950). The environmental effects, such as DES concentrations, pH levels, and temperature, on the strain’s degradation ability were tested. Degradation metabolites of DES by strain JF were analyzed via high performance liquid chromatography (HPLC) and liquid-chromatography time of flight mass spectrometry (LC-TOF-MS). Results indicated that B. subtilis JF can effectively degrade DES within a concentration of 25–200 mg/L. Increasing pH levels (pH > 7) are reported to increase the degradation rate of DES by the strain. The optimal temperature for strain JF to degrade DES was identified as 45°C. In this study, 4, 4′-hexene estrogen quinones (DESQ) and DES-4-semiquinone were speculated as two degradation metabolites of DES, and both can be completely degraded by strain JF. A slight reduction of DES in the blank system [DES cultured in Luria-Bertani (LB) medium without strain JF] was observed in this study. The reduction trend in the blank system only occurred during the first few days (about 4 days) and was considerably lesser than the decomposition and transformation effect of DES via strain JF. Furthermore, the metabolite DESQ could not be further decomposed in blank LB medium without strain JF. All the results demonstrate that complete degradation of DES in the fermentation broth occurs due to the function of strain JF rather than organic decomposition. In conclusion, the high efficiency of degradation and the potential to degrade DES completely indicates that strain JF has potential for the bioremediation of DES-contaminated environments (soil, river, and so on) and fermented foods.

Genital tract and reproductive characteristics in daughters of women and men prenatally exposed to diethylstilbestrol (DES)

Prenatal exposure of women to diethylstilbestrol (DES) has been associated with reproductive tract anomalies, menstrual irregularity, infertility and pregnancy complications. In prenatally exposed men, adverse effects included genital anomalies and possible risk of infertility. In children of prenatally exposed women, i.e the third generation, an increased incidence of genital defects was observed in sons (hypospadias), but not in daughters. In daughters of prenatally exposed men, the incidence of genital anomalies was in the normal range. Experimental studies in mice evidenced an increased incidence of reproductive tract anomalies in the female descendants of females and males prenatally exposed to DES, indicative of transgenerational transmission of DES defects. The aim of this study is to assess genital tract defects, fertility and pregnancy outcome, in daughters of women and men prenatally exposed to DES. In a retrospective observational analysis, 759 daughters of prenatally exposed women and men reported their genital and reproductive characteristics that were compared with those of: 1) general population in France; 2) two cohorts of daughters of exposed women reported in previous publications; 3) women prenatally exposed to DES. An increased incidence of uterine defects was observed, with both doubling of uterus and bicornuate and aplastic uterus which constitutes the Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS). No specific anomalies described in prenatally exposed women such as T-shape or hypoplastic uterus were reported. Infertility appeared to be in the normal range. Pregnancy outcomes of our 121 pregnancies of women born to DES exposed mothers and two other published cohorts presented inconsistent results for ectopic pregnancy, miscarriage and preterm delivery. Early and late miscarriages were higher than expected in general population in our cohort but not in the two others. These results must be considered as preliminary, due to the small numbers of patients, limited follow-up duration after birth due to young age of the studied population, and observational methods. An important point is that the high risk of reproductive dysfunction of women prenatally exposed to DES was not observed in their daughters. There is a signal on the high incidence of uterine defects, especially aplastic uterus, and its possible link with DES exposure through epigenetic effects is discussed in our findings. Inconsistent findings regarding pregnancy outcomes in the third generation are worthy of further examination.

Analysis of P53 Gene Mrna Expression and Caspase-3 Levels As Pre-Cervical Cancer Animals Model in Wistar Rat With Diethylstilbestrol-Induced

The use of hormones as one of the therapies is increasingly prevalent at this time, there are many uses obtained by hormone therapy such as preventing miscarriage in pregnant women or as a contraceptive. It was reported that the contraceptive hormone was the most used method by women compared to other contraceptive methods. Diethylstilbestrol (DES) is one of the synthetic estrogen hormones that is useful as hormone replacement therapy. However, the use of DES can also trigger abnormal cell growth that will develop into cervical cancer. This study was conducted to analyze the effect of DES on the p53 gene expression and caspase-3 levels. P53 is a cancer suppressor gene and caspase 3 is a gene that plays a vital role in the process of apoptosis. The method of this study was a post-test design in vivo experiment in animal model which was induced with doses of DES 1500 μgram / BB at 3 days of age after birth, then observed at 35 days. The results showed that there was a significant decrease in p53 gene expression and caspase-3 between DES-induced animals models compared with DES-uninduced with p-value = <0.05. Thus, it was concluded that DES has given to 3-day-old models animals and evaluate at the 35-days-old effect on decreasing p53 gene expression and caspase-3 levels.

One-pot hydrothermal synthesis of three-dimensional flower-like hollow Bi2WO6/reduced graphene oxide hybrid for sensitive photoelectrochemical detection of diethylstilbestrol

Flower-like hollow Bi2WO6 (FHBWO) nanoparticles were successfully synthesized and in-situ grown on the surface of reduced graphene oxide (RGO) to form a 3D structural FHBWO/RGO hybrid through a one-pot hydrothermal process. The obtained nanocomposites showed greatly improved photoactivity than pristine Bi2WO6. The photocurrent was 9 times enhanced because of the effectively accelerated electron transfer due to the adding of RGO. However, when diethylstilbestrol (DES) was added, the DES molecules would be absorbed onto the FHBWO/RGO surface, which could hinder the electron-transfer character greatly and resulted in the recombination of photo-generated holes and electrons leading to a prominent decrease in the photocurrent. Based on its outstanding photoelectrochemical (PEC) response and the inhibition effect of DES, a facile PEC sensor for the detection of DES was successfully developed in the concentration range from 0.1 pM to 1200 pM.

In vivo assessment of gonad status, secondary sex characteristics and spawning in transparent Casper zebrafish

Important aspects of vertebrate reproduction, such as gametogenesis, involve changes in organs found deep internally and thus not easily studied directly in most living vertebrates due to obscuring pigment and overlying tissues. Transparent lines of zebrafish, especially the Casper double mutant, allow direct observation and analysis of reproductive events in the gonads in vivo. The natural production of fertilized eggs in zebrafish is a complex process involving oogenesis, spermatogenesis, mating behavior, endocrine and neurological processes with inputs from the environment including light, temperature and nutrition. While these factors play important roles, the hypothalamic-pituitary-gonadal axis (HPGA) is central in the regulation of embryo output. Endocrine disrupting compounds (EDCs) include a variety of pollutants often present in the environment. EDCs may have direct effects on the HPGA or indirect effects through toxic action on supporting organs such as the liver or kidney. Estrogenic compounds such as diethylstilbestrol (DES) have been reported to affect reproduction in a variety of species including man. In this study, the effects of DES on reproduction were determined in a novel way by using transparent Casper zebrafish that allow direct visualization of gonad status over time. Changes in gonad status with DES treatment were correlated with effects on secondary sex characteristics (i.e., genital vent size and breeding tubercles) spawning and embryo production. The results suggest that the Casper zebrafish is a useful model for studying dynamics of reproductive events in vertebrate gonads in vivo and for determining effects of EDCs on zebrafish reproduction.

Grandmaternal pregnancy endocrine disruption, low birth weight, and premature birth

OPS 16: Chemical exposures and birth outcomes, Room 114, Floor 1, August 28, 2019, 10:30 AM - 12:00 PM Background/Aims Low birth weight (LBW; <2500g) and premature birth (<37 weeks) are major determinants of illnesses later in life. Diethylstilbestrol (DES), an endocrine disrupting chemical (EDC), is a synthetic, nonsteroidal estrogen. It was administered to nearly two million pregnant women in the US alone through the early 1970s, under the mistaken belief that it would prevent pregnancy complications and miscarriages. Though several studies recently have linked prenatal exposure to other EDCs and risks of LBW and premature birth, no three-generation studies examine the association between grandmaternal exposure to endocrine disruptors in pregnancy and risks of these outcomes in grandchildren. Methods: We analyzed data from Nurses’ Health Study (NHS) II participants (born 1946-1964). In 1993, nurses (F1) were asked whether their mother (F0) used DES during her pregnancy with them. Nurses’ children’s (F2) birth weight was queried in 2001. In the present study, we defined LBW as <5.5 pounds. Data were analyzed using cluster-weighted generalized estimating equations with a logit link. Results: Among 47,321 F0 grandmother-F1 mother pairs the prevalence of F0 use of DES during pregnancy was 1.85%. Of 106,631 F2 children, 3,808 (3.57%) were categorized as LBW and 6892 (6.48%) premature. Grandmaternal use of DES during pregnancy was associated with an increased risk of LBW (adjusted odds ratio [aOR] =1.60; 95% CI: 1.23-2.08) and prematurity (aOR=2.67; 95% CI: 2.21-3.21) among grandchildren even after accounting for potential mediating factors, such as F1 mother’s birth weight. The LBW association attenuated after adjusting for gestational age. Conclusion: Maternal prenatal exposure to DES is associated with an increased risk of premature birth and LBW even after adjusting for gestational age. This suggests a relation with both premature birth and intrauterine growth.

Voltammetric Determination of Diethylstilbestrol in Pharmaceutical Formulation

A simple, inexpensive and highly sensitive new electrochemical method was developed to quantify Diethylstilbestrol (DES) in medication samples using carbon paste electrode (CPE). The electrode was electrochemically characterized using cyclic voltammetry (CV) and square wave voltammetry (SWV). From the cyclic voltammograms obtained in the presence of diethylstilbestrol could be observed two peaks, one of oxidation at ≈ 590 mV and other of reduction at 200 mV. The development of method for estrogen quantification under study involved optimization of instrumental parameters (frequency, amplitude and potential step) and the experimental parameter pH. The electrochemical procedure applied to diethylstilbestrol was developed using CPE under optimal conditions. Diethylstilbestrol oxidation currents exhibited linear concentration in the 0.017 - 2.08 mmol L -1 range, with a limit of detection of 14.15 nmol L -1 . The amount of DES found in the analyzed samples was 0.98 mg, with a relative standard deviation of less than 2%, indicating high agreement with the amount described in the label of the drug (1 mg). The results indicate that the method is applicable for quantifying diethylstilbestrol in pharmaceutical formulation. DOI: http://dx.doi.org/10.17807/orbital.v11i4.1326