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.

Development and validation of a confirmatory method for the determination of stilbene estrogens in ostrich serum.

A simple and accurate ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the first time as a confirmatory method for the simultaneous determination of stilbenes - hexestrol and diethylstibestrol in serum. Extraction was based on a simple acid denaturation of protein followed by liquid-liquid extraction using methyl tert butyl ether. Extracts were directly injected into the UHPLC-MS/MS without further purification. Excellent recoveries in the range 82-99% and 91-128% were obtained for hexestrol and diethylstibestrol, respectively. Both within-day repeatability and between-day reproducibility were generally satisfactory with RSD <20%. The linearity of the internal standard based matrix-matched calibration curve measured as the coefficient of regression (r2) was generally >0.99 for both hexestrol and diethylstibestrol. Both matrix effect and uncertainties associated with sample preparation and instrumental analysis were significantly reduced with the use of a deuterated compound (hexestrol-d4) as internal standard. The LOD and LOQ were 0.09 and 0.08 ng/ml, and 0.28 and 0.25 ng/ml, respectively, for hexestrol and diethylstibestrol. The method was found to be suitable for the simultaneous determination of hexestrol and diethylstibestrol in serum.

Pharmacokinetics and safety profiles of novel diethylstilbestrol orally dissolving film in comparison with diethylstilbestrol capsules in healthy Chinese male subjects.

OBJECTIVE: We compared the pharmacokinetic (PK) profiles of diethylstilbestrol orally dissolving film (DES ODF) and DES-capsule as well as assessing the safety, local tolerability, taste, and disintegration time of DES ODF. MATERIALS AND METHODS: Twelve healthy male volunteers receiving a single administration of 2.0 mg of DES ODF or DES-capsule were included in the study. The tolerability, taste, and time to dissolution of DES ODF were assessed after dosing. Safety assessments included adverse events, hematology and biochemistry tests, urinalysis, vital signs, and electrocardiography. RESULTS: The PK parameters of DES ODF were all greater than those of DEScapsule. The Cmax values were 5.64 ± 1.1 and 3.4 ± 1.93 ng/mL for DES ODF and DES-capsule, respectively. Assessment of bioequivalence was based on the 90% CIs of the treatment ratios of the log-transformed Cmax, AUC0-t, and AUC0-∞ (DES ODF to DES-capsule), with the mean values being 1.93 (141 - 264), 1.24 (98 - 156), and 1.59 (121 - 207), respectively, indicating that DES ODF had a significantly high bioavailability. The mean DES ODF disintegration time was 14 ± 5 minutes. DES ODF was well tolerated and no serious adverse events or clinically relevant changes were observed. CONCLUSIONS: The DES ODF is well tolerated and better absorbed in comparison with DES-capsule.

[Analysis of six phenolic environmental estrogens in bullfrog blood by using dispersive solid-phase extraction and ultrafast liquid chromatography-tandem mass spectrometry].

A rapid, sensitive and accurate method for the simultaneous determination of six phenolic environmental estrogens, i. e., bisphenol A (BPA), diethylstilbestrol (DES), dienestrol( DE), hexestrol (HEX), 4-( tert-octyl)-phenol (4-tOP) and 4-nonylphenol (4-NP) in bullfrog blood by dispersive solid-phase extraction-ultrafast liquid chromatography-tandem mass spectrometry (dSPE-UFLC-MS/MS) was established. After protein precipitation, bullfrog blood samples were cleaned-up by dSPE method with ethylenediamine-functionalized Fe3O4, magnetic polymers (EDA-MPs) as adsorbent. The effects of precipitation solvents, adsorption time and the amount of EDA-MPs used on the recoveries of six phenolic environmental estrogens were investigated in detail. Chromatographic separation was performed on a Shim-pack XR-ODS II analytical column (100 mm x 2.0 mm, 2.2 microm). The mass spectrometer was operated by using electrospray ion (ESI) source in the multiple reaction monitoring (MRM) mode. The results showed that the linearities were in the range of 0.5-100.0 microg/L with correlation coefficients (r2) not less than 0.999 6 for all the six phenolic environmental estrogens. The lim- its of quantification (LOQs) (S/N > 10) in bullfrog blood samples were between 0. 075 microg/L and 0.40 microg/L. The recoveries were between 95.0% and 110.0% at three spiked levels. The precision values expressed as relative standard deviations (RSDs) were in the range of 0.6%-6.3%. The developed method can be applied to the routine analysis of the six phenolic environmental estrogens in bullfrog blood samples.

Interaction of diethylstilbestrol and ioxynil with transthyretin in chicken serum.

The association of suspected endocrine-disrupting chemicals (EDCs), diethylstilbestrol (DES), ioxynil and pentachlorophenol (PCP), with chicken serum proteins was investigated in relation to thyroid system disruption. All of these chemicals strongly inhibited l-[(125)I]thyroxine ([(125)I]T(4)) binding to purified transthyretin (TTR) whereas PCP was less potent inhibitor than DES and ioxynil of [(125)I]T(4) binding to diluted whole chicken serum. This result suggested that PCP interacted with serum proteins other than TTR in whole chicken serum. Following the incubation of chicken serum with each chemical (final concentrations 0.25-1.0 microM), serum proteins were fractionated by gel filtration chromatography (Cellulofine GCL-1000) and affinity chromatography (human retinol-binding protein coupled to Sepharose 4B). Although all chemicals were detected in the gel filtration chromatography 50-100 kDa fractions, DES and ioxynil, but not PCP, were co-eluted with TTR during affinity chromatography. Our results indicated that a significant proportion of DES and ioxynil, but a low proportion of PCP, interacted with TTR in whole chicken serum.

Differential effects of the endocrine-disrupting compounds bisphenol-A and octylphenol on gonadotropin secretion, in prepubertal ewe lambs.

This study examined the effects of long-term exposure to the endocrine-disrupting compounds (EDCs) Bisphenol-A (BPA) and Octylphenol (OP) on gonadotrophin secretion in pre-pubertal female sheep. Four-week-old, female lambs were randomly allocated to four groups (n=6), and twice each week treated with i.m. injections of either corn oil (vehicle controls), diethylstilbestrol (DES; 0.175mg/kg), BPA (3.5mg/kg) or OP (3.5mg/kg). After 5 weeks of treatment, animals were ovariectomized (ovx) and ovary weights recorded. Two weeks later, blood samples were collected from lambs every 15min for 6h, for LH pulse analysis. Animals were then euthanased and adrenal and kidney weight recorded. An age-related increase in tonic LH secretion was noted in Control, BPA- and OP-treated lambs, but was absent in DES-treated lambs. Following ovx, LH secretion increased in all except DES-treated lambs; FSH concentrations increased in all groups. BPA and DES significantly suppressed LH pulse frequency (C: 6.7+/-0.3pulses/6h, DES: 1.5+/-0.8pulses/6h, BPA: 2.3+/-0.8pulses/6h) and amplitude (C: 7.1+/-1.0ng/ml, DES: 1.9+/-0.6ng/ml, BPA: 1.6+/-0.4ng/ml). OP had no effect on LH secretion (Frequency: 5.8+/-0.5pulses/6h, amplitude: 8.0+/-2.0ng/ml). Ovary weight was similar among all groups. Results show that chronic in vivo exposure of prepubertal female lambs to BPA, at levels lower than those reported previously, can have significant effects on LH secretion that are comparable to those seen following exposure to the known xenoestrogen, DES. Exposure to an equal dose of the EDC OP, over the equivalent period of time was without effect on gonadotropin secretion in the prepubertal ewe lamb. These results indicate that exposure of prepubertal female lambs to the EDC BPA can induce significant effects on gonadotropin secretion, the potential long-term effects of exposure and the effects of these changes on reproductive performance and efficacy, therefore, merit further study.

Voltammetric investigation of diethylstilbestrol.

In this work electrooxidation of diethylstilbestrol (DES) was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) using a glassy carbon (GC) electrode. It was statistically shown that both methods could be used for the determination of DES in the concentration range of 2 x 10(-5)-6 x 10(-4) M by CV and 1 x 10(-5)-1 x 10(-3) M in methanol (MeOH) and 4 x 10(-5)-6 x 10(-4) M in acetonitrile (ACN) by DPV and both of the methods could be applied to human serum. A mechanism was proposed about the electrooxidation of this substance.

Development of the blood-testis barrier in the mouse is delayed by neonatally administered diethylstilbestrol but not by beta-estradiol 3-benzoate.

A group of newborn mice were treated with 1 micro g dose-1 individual-1 of diethylstilbestrol (DES) on alternate days, from days 1 to 11 postnatally. Another group of mice were treated similarly with 125 ng dose-1 individual-1 of beta-estradiol 3-benzoate (E2B). The testes were sequentially examined up to 84 days of age using light and electron microscopy. Spermatogenic cells in the DES-treated mice differentiated normally from birth until 17 days of age, when they differentiated into pachytene spermatocytes and remained at this meiotic prophase for the next 10 days approximately. The cells then began to differentiate further, ultimately forming spermatozoa by 49 days of age. Confocal and electron microscopy showed that the blood-testis barrier did not form until 28 days of age in the DES-treated mice, and a delay in the functional maturation of this structure, as the blood-testis barrier, was confirmed by intercellular tracer experiments. The arrest of spermatogenesis at the meiotic prophase may have been attributable to the DES-induced defective formation of the blood-testis barrier. No delay of the blood-testis barrier formation was detected in the E2B-treated mice. Thus, DES and E2B, both of which are known as potent oestrogenic compounds, had different effects on the Sertoli cells.

The pharmacokinetics of fosfestrol and diethylstilbestrol in chronic hemodialysis patients with prostate cancer.

BACKGROUND: Fosfestrol drip infusion therapy is an available endocrinotherapy for prostate cancer. But since there have been few reports of its use in chronic dialysis patients, the pharmacokinetics of fosfestrol in these patients remains unclear. We conducted fosfestrol drip infusion therapy as an induction therapy in chronic hemodialysis patients with prostate cancer. METHODS: Two male patients were included in this study. One was a 68-year-old man who had been in hemodialysis for 15.7 years and had stage B2 prostate cancer. The other was a 74-year-old man who had been in hemodialysis for 4.4 years and had stage C prostate cancer. A total of 250 mg of fosfestrol was dissolved in 250 mL of 5% glucose solution and administered by drip infusion. The drug was given subcutaneously during 14 consecutive days and a luteinizing hormone-releasing hormone agonist was injected on day 15. RESULTS: Serum fosfestrol levels increased rapidly after the drip infusion was started and remained at high levels during infusion, but fell quickly after the treatment ended. Diethylstilbestrol (DES) was also detected in blood after the infusion was started and its levels peaked when infusion ended. But on the next day, neither fosfestrol nor DES were detected in the blood of the patients. Moreover, neither fosfestrol nor DES was detected in the blood of the two patients before administering fosfestrol on day 15. Fosfestrol was quickly eliminated from the blood after hemodialysis was started, while DES remained in the blood during hemodialysis. The adverse reactions were mild hepatic dysfunction and gynecomastia. CONCLUSIONS: Fosfestrol drip infusion therapy appeared to be safe as an endocrinotherapy for prostate cancer in chronic hemodialysis patients.

Sexual dimorphism in diethylstilbestrol-induced prolactin pituitary tumors in F344 rats.

Female F344 rats treated chronically with diethylstilbestrol (DES) develop prolactin (PRL)-producing pituitary tumors. These tumors are larger in female than in male rats. To investigate gender differences in DES-induced pituitary tumor formation, we employed female and male rats and neonatally androgenized females, which received 100 microg of testosterone propionate (TP) after birth. At 3 months of age, all rats were deprived of their gonads and divided into control and DES-treated groups. Forty days after beginning treatment, control pituitary weight and serum PRL were similar in gonadectomized males (GDX), ovariectomized females (OVX) and androgenized-ovariectomized females (OVX + TP), but weight of DES-induced tumors was 2.5-fold higher and serum PRL 5.6-fold higher in OVX + DES than in GDX + DES or OXV + TP + DES (p<0.001). At the pituitary level, nuclear estrogen receptors (NE(2)R) amounted to >100 fmol/mg DNA in all rats receiving DES. However, NE(2)R were lower in OVX + DES (101.3+/-9.0 fmol/mg DNA) than in GDX + DES (174.6 +/-16.8; p<0.05) and in OXV + DES + TP (150.3+/-27.7; p<0.05). A similar profile was found for cytosolic progestin receptors. Using electron microscopy (EM), hyperplasia/hypertrophy of lactotropes was found in all DES-stimulated pituitaries. However, tumors of OVX + DES rats were enriched in hyperstimulated typical lactotropes, i.e., cells with high rate of hormonal synthesis, processing and secretion. Instead, tumors from GDX + DES and OVX + TP + DES rats were a mixture of typical and atypical lactotropes, i.e. a cell subpopulation with refractory secretory response and a few gonadotropes. In agreement with these data, immunoreactive pituitary PRL was lower in OVX + DES than in OVX + TP + DES and GDX + DES groups. Thus, differences in the sensitivity to DES, serum and tumor PRL, NE(2)R and progestin receptors between estrogenized female rats on one side and male and TP-androgenized females on the other, may by due in part to heterogeneity of cell populations. Our data further suggest that neonatal hypothalamic exposure to androgens, as in normal males or androgenized females with masculinization of hypothalamic centers, may condition the response to DES stimulation later in life.

Telarquia prematura: aumento de la actividad estrogénica total en el plasma / Premature thelarche: increased of total estrogenic activity in the serum

Con el propósito de estudiar las causas de la telarquia prematura, se comparó el perfil hormonal y las características de los genitales internos mediante ultrasonografía pelvians en 41 niñas afectadas, de 21,15 ñ 9,74 meses de edad y e 31 controles de la misma edad y nivel socioeconómico y se buscó contaminación de los alimentos con zearalenona y dietilbestrol por cromatografía en capa delgada. La actividad estrogénica total en el plasma de las niñas, así como plasma y tejidos de pollo, se midió por el método de radiorreceptor. Las concentraciones basales de LH, FSH, prolactina y estradiol eran similares en pacientes y controles. La actividad estrogénica total fue significativamente mayor en las niñas con telarquia (201 ñ 102 vs 78 ñ 20 pg E2 equivalente) y descendió a niveles similares que en los controles (75 ñ 8 pg E2) al desaparecer la telarquia. La respuesta a LHRH en pacientes con telarquia fue mayor para FSH (28,7 ñ 17,5 Uµ/ml) que para LH (5,01 ñ 2,7 Uµ/ml). El tamaño del útero y la maduración ósea fueron similares en ambos grupos, pero el volumen ovárico medio fue mayor en pacientes con telarquia. No se detectaron contaminantes exógenos en la sangre de las niñasy los tejidos de 25 pollos. La actividad estrogénica en el plasma de las aves cumplía las recomendaciones internacionales (FAO). La respuesta de FSH al factor liberador, el mayor volumen ovárico y el aumento de la actividad estrogénica sugieren activación parcial del eje hipotálamo-hipofisiario-gonadal de predominio FSH en las niñas con telarquia prematura

A 125I-radioimmunoassay for diethylstilbestrol in serum of patients with prostatic cancer treated with stilphostrol.

A new radioimmunoassay for determining diethylstilbestrol in serum using N-(4'-OH-[3'-125I]iodophenethyl)-6-(4-O-diethylstilbestryl)-hex anamide as a radiotracer and a double antibody as a separation reagent is described. The radiotracer is prepared by synthesizing 6-(4-O-diethylstilbestryl)-hexanoic acid and coupling its succinimidyl ester with mono-[125I]tyramine in tetrahydrofuran (16 h, 20-22 degrees C). The standard curve is linear (semi-log transformation) and the assay is sensitive (< 0.022 pmol/tube), reproducible (intra- and interassay coefficient of variation values, 5.3 and 8.1%, respectively), and accurate (recovery values, 95-101%), with a non-specific binding less than 3.2%. Diethylstilbestrol concentrations measured in sera of nine patients with prostatic cancer by the proposed assay ranged from 0.170 to 2.517 mumol/l, which corresponded to an only three-fold dosage variation. In all cases tested, dosing was adequate to retain markers of prostatic cancer in serum within accepted limits; nevertheless, individualization of dosing may be necessary to minimize toxicity.

Improved thin-layer chromatographic detection of diethylstilbestrol and zeranol in plasma and tissues isolated with alumina and ion-exchange membrane columns in tandem.

Clean-up procedures for the isolation of zeranol and diethylstilbestrol (DES) were modified to reduce the analysis time and to increase the efficiency of purification. Several dyes (Fast Blue BB, Fast Corinth V, Fast Blue RR, Fast Blue B, Fast Red Violet B and Fast Violet B) were evaluated, and their minimum detectabilities were determined. Conditions for non-instrumental, semi-quantitative thin-layer chromatography were optimized. Zeranol and DES in plasma and tissues were determined using modified procedures. Enzyme digestion brought about significant improvement in detectabilities of zeranol and DES in both fortified and incurred plasma, serum and tissues. Minimum detectabilities for zeranol and DES were 25 ppb in fortified plasma and tissues. The amount of incurred zeranol measured in the serum of an experimental cow was increased four times, i.e. from 50 to 200 ppb, after protease digestion. Glucuronidase digestion showed an eight-fold increase in detection of incurred zeranol levels in bovine liver eight times. These results suggest that digestion releases zeranol and DES from protein and glucuronide complexes, thereby allowing detection of low levels of zeranol and DES which may not be detectable without digestion. Further modification of the purification with an ion-exchange membrane reduced the analysis time by 25%, and the membranes were regenerated up to ten times without loss of activity, allowing an automated process. This method utilizes inexpensive equipment and avoids use of organic solvent, in this case diethyl ether.

Direct radioimmunoassay for diethylstilbestrol in serum.

A radioimmunoassay method for the measurement of diethylstilbestrol directly on 50 microliters of human serum was established using a tritium-labeled radioligand and a double antibody as a separation reagent. The assay was sensitive (less than 0.17 micrograms/L), reproducible (intra-assay and interassay coefficient of variation values, 8.14% and 8.25%, respectively), and accurate (recovery up to 95%). Factors influencing the assay are identified and discussed.

The uptake of tritiated diethylstilbestrol by the brain, pituitary gland, and genital tract of the fetal macaque: a combined chromatographic and autoradiographic study.

To examine the possible sites of action of the synthetic estrogen diethylstilbestrol (DES) in the developing primate, [3H]DES (250 mu Ci, iv, or 500 mu Ci, sc) was administered directly into two rhesus and nine cynomolgus macaque fetuses at about 122 days gestation (range, 121-124 days). The location of cells accumulating radioactivity 60 min later was examined by autoradiography in two males and two females. In females, labeled neurons were observed in the hypothalamus, preoptic area, and amygdala, but not in the cerebral cortex. In one male a similar pattern of uptake was observed, but percentages of labeled neurons were lower, and in the other male very little labeling was observed in any region. The chemical identity of the radioactivity in cell nuclei was determined by high performance liquid chromatography in three males and four females. Concentrations of radioactivity in nuclear pellets were highest in the hypothalamus and lowest in the cerebral cortex. This regional variation was highly significant (P less than 0.001), but there was no significant difference between nuclear concentrations of radioactivity in males and females. In supernatant fractions, concentrations of radioactivity showed no significant variation between brain regions and after 60 min, 52-67% of the extracted radioactivity was no longer in the form of [3H]DES. Nuclear levels of radioactivity in pituitary glands and genital tracts of both male and female fetuses were 2-5 times higher than those in hypothalamus. The results demonstrated a direct interaction between DES and cell nuclei from specific regions of the brain, pituitary gland, and genital tract at this stage of gestation in a primate.

Analysis of diethylstilbestrol, dienestrol and hexestrol in biological samples by immunoaffinity extraction and gas chromatography-negative-ion chemical ionization mass spectrometry.

A method has been developed for the detection of diethylstilbestrol, together with dienestrol and hexestrol, using extraction with a single immunoaffinity column containing antibodies raised against diethylstilbestrol, followed by gas chromatography-negative-ion chemical ionization mass spectrometry. Immunoaffinity columns were prepared by coupling immunoglobulin G fractions obtained from rabbit antisera with a Sepharose matrix. The immunizing agent was synthesized by introducing a carboxyl group into the diethylstilbestrol molecule and coupling this product to bovine serum albumin. The columns were used for immunoadsorption of diethylstilbestrol and other estrogens, after dilution of samples with phosphate buffer, and were eluted with acetone-water (95:5 v/v). A derivatization method suitable for gas chromatographic-mass spectrometric analysis of diethylstilbestrol and other estrogens was developed using pentafluorobenzyl bromide and ethanolic potassium hydroxide as reagents. The derivatives obtained were detectable at the sub-picogram level using gas chromatography with negative-ion chemical ionization mass spectrometry. Recoveries of cis- and trans-diethylstilbestrol, dienestrol and hexestrol from the immunoaffinity columns, determined after extraction from urine, plasma and buffer, ranged from 28 to 96%. The sensitivity for diethylstilbestrol in urine samples was ca. 10 ppt. The method was applied to the analysis of urine from calves given a single dose of 10 mg of diethylstilbestrol. Free and glucuronic acid conjugated diethylstilbestrol decreased with time, but their ratio was variable.

Medical castration using megestrol acetate and minidose estrogen.

Sixty-two men who presented with previously untreated metastatic carcinoma of the prostate (D0: 10 patients; D1: 29 patients; D2: 23 patients) received oral megestrol acetate (80 mg twice daily) and minidose estrogen (diethylstibestrol 0.1 mg or ethinyl estradiol 0.05 mg once daily) as a means of achieving total androgen ablation (testicular and adrenal). A high incidence of feminizing side effects (70-74%), a higher than expected rate of cardiovascular complications (18%), an unexpected need for cortisone replacement (13%), and failure of patients with Stage D2 disease to obtain results better than those of standard therapy during the first year of observation suggest this regimen offers no advantage over other more conventional therapy.

Effect of diethylstilbestrol diphosphate on activity of 5 alpha-reductase in human prostate.

Following the intravenous drip infusion of diethylstilbestrol diphosphate (DES-DP), the diethylstilbestrol (DES) concentrations both in plasma and prostatic tissue obtained from patients with prostatic carcinoma were measured by radioimmunoassay and the effects of DES on the activity of 5 alpha-reductase in the prostate obtained from BPH patients were determined in vitro. Further, the changes in the activity of 5 alpha-reductase in the prostate from the BPH patients who received DES-DP infusion were also determined. The plasma and prostatic tissue concentrations of DES rapidly declined from 2.3 micrograms/ml and 1.6 micrograms/g wet weight 1 h after DES-DP infusion to 0.8 microgram/ml and 0.25 microgram/g wet weight 3 h after DES-DP infusion, respectively, and decreased gradually thereafter until 24 h. In in vitro study progressed by BPH specimens, the 5 alpha-reduction rate was completely inhibited by an addition of 5 x 10(-4) M of DES and the DES concentration on the inhibition rate of 50% was 4 x 10(-5) M. In in vivo study, the mean production rate of 5 alpha-dihydrotestosterone (DHT) in the control specimens of BPH without infusion of DES-DP was 14.0 +/- 3.4 nmol/15 min/mg protein and the production rate of DHT in the DES-DP infused specimens of BPH was 14.7 nmol/15 min/mg protein at 3 h and 15.2 nmol/15 min/mg protein at 12 h after the termination of DES-DP infusion. These results indicated that intravenously administered DES-DP did not act via the inhibition of 5 alpha-reductase in the prostatic cells for producing the clinical effects.