Regular ArticleDevelopmental Effects of an Environmental Antiandrogen: The Fungicide Vinclozolin Alters Sex Differentiation of the Male Rat
Abstract
In humans and rodents, exposure to hormonally active chemicals during sex differentiation can produce a wide range of abnormal sexual phenotypes including masculinized and defeminized females and feminized and demasculinized males. Although numerous "environmental estrogens," including pesticides, toxic substances (PCBs), and plant and fungal estrogens, have been shown to alter mammalian sex differentiation, similar information on environmental androgens is lacking. Recently, the fungicide vinclozolin (V) was found to inhibit sexual differentiation in male rats in an antiandrogenic manner. In the present study, V was administered to pregnant rats (po) at 0, 100, or 200 mg/kg/day in corn oil during the period of sex differentiation (Gestational Day 14 to Postnatal Day 3) to examine the demasculinizing effect of this fungicide more closely. In both groups of V-treated male offspring, anogenital distance was female like at birth, and nipple development was prominent at 2 weeks of age. After puberty, most of the V-treated male offspring were unable to attain intromission even though they all mounted sexually receptive females. The V-treated male offspring that appeared to achieve intromission, failed to ejaculate normally, as no sperm were found in the uterus after overnight matings. A factor in the abnormal ejaculation was that all V-treated male offspring had cleft phallus with hypospadias. In addition, a number of unusual reproductive malformations were noted when the males were necropsied at 1 year. Many V-treated male offspring had suprainguinal ectopic scrota/testes, a vaginal pouch, epididymal granulomas, and small to absent sex accessory glands. During the study, about 25% of the V-treated males died as a result of bladder stones, hydroureter, or hydronephrosis, while other males displayed these lesions at necropsy. While some of the above malformations in male offspring can also be produced by perinatal administration of a potent estrogen, like DES, V-treated female offspring did not display any estrogen-like alterations of reproductive development or fecundity. The only change seen in the female offspring was a reduced anogenital distance during neonatal life. Our observation of perinatal-induced agenesis of the prostate and blocked testicular descent, a pattern of malformations nearly identical to that reported for the antiandrogen flutamide, is consistent with other recent evidence that this fungicide is an androgen-receptor antagonist.
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Azole fungicides inhibit human and rat gonadal 3β-hydroxysteroid dehydrogenases: Structure-activity relationship and in silico docking analysis
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Exploring associations between residential exposure to pesticides and birth outcomes using the Dutch birth registry
2023, Environment InternationalMaternal occupational exposure to pesticides has been linked to adverse birth outcomes but associations with residential pesticide exposures are inconclusive.
To explore associations between residential exposure to specific pesticides and birth outcomes using individual level exposure and pregnancy/birth data.
From all 2009–2013 singleton births in the Dutch birth registry, we selected mothers > 16 years old living in non-urban areas, who had complete address history and changed addresses at most once during pregnancy (N = 339,947). We estimated amount (kg) of 139 active ingredients (AI) used within buffers of 50, 100, 250 and 500 m around each mother's home during pregnancy. We used generalized linear models to investigate associations between 12 AIs with evidence of reproductive toxicity and gestational age (GA), birth weight (BW), perinatal mortality, child́s sex, prematurity, low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA), adjusting for individual and area-level confounders. For the remainder 127 AIs, we used minimax concave penalty with a stability selection step to identify those that could be related to birth outcomes.
Regression analyses showed that maternal residential exposure to fluroxypyr-meptyl was associated with longer GA, glufosinate-ammonium with higher risk of LBW, linuron with higher BW and higher odds of LGA, thiacloprid with lower odds of perinatal mortality and vinclozolin with longer GA. Variable selection analysis revealed that picoxystrobin was associated with higher odds of LGA. We found no evidence of associations with other AIs. Sensitivity and additional analysis supported these results except for thiacloprid.
In this exploratory study, pregnant women residing near crops where fluroxypyr-meptyl, glufosinate-ammonium, linuron, vinclozolin and picoxystrobin were applied had higher risk for certain potentially adverse birth outcomes. Our findings provide leads for confirmatory investigations on these compounds and/or compounds with similar modes of action.
Multiplex planar bioassay with reduced diffusion on normal phase, identifying androgens, verified antiandrogens and synergists in botanicals via 12D hyphenation
2022, Food ChemistryHormonal active compounds affecting health by altering the hormonal system are present in food. The planar yeast antagonist androgen screen (pYAAS) bioassay is a powerful tool to detect individual hormonal active compounds in complex samples separated by high-performance thin-layer chromatography (HPTLC). Previous methods lacked either detection sensitivity or zone sharpness. To overcome diffusion caused by long bioassay incubation on the normal–phase (NP) plate, zone fixation (fix) was achieved with a new polyisobutyl methacrylate coating, leading to enhanced zone sharpness. The exclusion of false-positive antagonists was integrated in the workflow, which allowed the verification (V) of true antagonists, apart from the detection of synergists. With the new multiplex bioassay providing information on 4 activities, 68 different botanicals were screened and hormonal active zones were identified by elution from the bioautogram to orthogonal reversed-phase high performance liquid chromatography with diode array detection and high-resolution mass spectrometry including fragmentation, resulting in the 12D hyphenation NP-HPTLCfix–UV/Vis/FLD–pYAVAS–FLD–heart cut–RP-HPLC–DAD–HRMS/MS.
Intracellular distribution of vinclozolin and its metabolites differently affects 5α-dihydrotestosterone (DHT)-induced PSA secretion in LNCaP cells
2022, Reproductive ToxicologyEndocrine disruption mechanisms in prostate are an overlooked issue. The anti-androgenic properties of the fungicide vinclozolin (VIN) and its active metabolites - 2-[[(3,5- dichlorophenyl)-carbamoyl]oxy]− 2-methyl-3-butenoic acid (M1) and 3’5’-dichloro-2-hydroxy-2- methylbut-3-enanilide (M2) - were assessed on human prostate-derived cells (LNCaP); the effects were investigated also upon co-treatment with 5α-dihydrotestosterone (DHT), the physiological androgen receptor (AR)-agonist, and compared to the anti-androgenic drugs, 2-hydroxy-flutamide (2OH-FTA) and bicalutamide (BIC). Assessed endpoints were the cellular uptake and subcellular localization of VIN, M1 and M2, DHT-induced PSA gene expression and secretion. VIN, its metabolites, and the reference drugs, significantly reduced DHT-induced PSA secretion and gene expression, M2 showing the strongest downregulation. In absence of DHT, 2OH-FTA and BIC showed a very high (>98%) LNCaP uptake with a predominant intranuclear localization (BIC=80%, 2OH-FTA=70%). VIN cellular uptake was 42%: 24.7% made up by M2, mostly localized at nuclear level, differently from VIN and M1. Upon DHT co-treatment, VIN intracellular uptake increased by 28%, especially in the microsomal fraction (MF); M2 also increased mainly in MF but also, to a lower extent, in the intranuclear fraction. Finally, in a 72-hr time-course, the LNCaP uptake of VIN and its metabolites was much faster compared to purified M1 and M2. Overall, M2 resulted the leading compound for VIN endocrine-disrupting effects in LNCaP.
Herbicides and fungicides
2022, Reproductive and Developmental ToxicologyThis chapter describes the reproductive and developmental toxicity of herbicides and fungicides in humans and animals. Numerous chemicals including herbicides and fungicides are ubiquitous in the environment. Some of them obviously have the potential to cause reproductive and developmental toxicity. Most of the data presently available have been derived from experiments performed on laboratory species or in vitro models. Epidemiological studies clearly indicate that exposure to these chemicals may be associated with menstrual cycle disturbances, reduced fertility, prolonged time to pregnancy, spontaneous abortions, stillbirths, and developmental defects both in animals and humans. The number of herbicides and fungicides having endocrine disruptor properties is increasing. Several such chemicals are still under investigation. Therefore, several herbicides and fungicides are known to cause reproductive toxicity, developmental problems, and endocrine disruptions in animals and humans.