Project description:Purpose: In testis the effects of exposure to mixtures of Endocrine disruptors compounds (EDCs) upon expression of miRNAs were not addressed. Objective: To identify the expression profiles of the 'miRNome' in mice testis chronic exposed to a defined mixture of five EDCs. Methods: Pregnant mice from 0.5 post-coital day were exposed in the drinking water to a mixture containing 0.3 mg/Kg-bw/day of each phthalate (DEHP, DBP, BBP), plus 0.05 mg/Kg-bw/day of each alkylphenol (NP, OP) until adulthood of male mouse (60 days old). We characterized the 'miRNome' by next generation sequence (NGS). Results: In mouse testis exposed to EDCs mixture we detected by NGS 2 up-regulated and 8 down-regulated miRNAs along to 36 isomiRs differentially expressed; these results were validated by RT-qPCR. and functional analysis showed deregulation of testicular hormonal status, spermatogenesis disruption and germ cells apoptosis. Conclusions: Here we provide the first association between deregulation of miRNAs, isomiRs, with histopathological and hormonal alterations in adult mice testis exposed to mixture of EDCs.
Project description:Environmental reproductive health focuses on the effect of exposure to contaminants considered as endocrine disruptors. Developmental testis is considered as target of these compounds affecting testicular functions in adults and suspected implications in tumor etiology. Comparative analysis of gene expression in mouse testis exposed to five disruptors, three different dosages and three accumulative developmental stages shown defined signature profiles of gene deregulation for MEHP (monoethyl phthalate) and zearalenone (a phytoestrogen) and different to 17β-estradiol exposure. The effects are even detected in postpuberal male offspring from premating exposed mothers. Oxidative stress response, protein ubiquitination and oxidative phosphorylation are the most representative pathways affected.
Project description:Despite the fact that we are constantly exposed to various environmental compounds, very few studies explore the impact of combined exposure to physical and chemical pollutants on reproductive health. Until now, assessment of pollutants is mostly based on the evaluation of single pollutant or combination of chemicals with common features and modes of action. In this context, numerous studies have demonstrated that steroidogenesis and gametogenesis, the main testicular functions, are well-known to be sensitize by endocrine disruptors (as Bisphenol A) and DNA-damaging agents (as γ-rays) respectively. In this study, we aim to investigate short and long term testicular transcriptionnal alterations of combined fetal exposure to well-known environmental toxicants: γ-rays (RAD) and BPA. To discriminate specific signatures of BPA or RAD exposure after combined exposure and evidence the type of synergisms between this pollutants, we performed transcriptomic analyses on testis exposed to BPA or RAD alone and co-exposed with BPA and RAD and compared gene expression with control condition. For this, we exposed pregnant mice from 10.5 dpc to 18.5 dpc to 10µM of BPA (in drinking water) and/or we irradiated mice at 12.5 dpc to 0.2 Gy. We performed transcriptomic analyses on fetal testis (18.5 dpc) and adult testis (3 months) to evaluate short and long term cell response after in utero exposure.
Project description:Endocrine disrupting chemicals (EDCs) are man-made compounds that alter functions of the endocrine system. Environmental mixtures of EDCs might have adverse effects on human health, even though their individual concentrations are below regulatory levels of concerns. However, studies identifying and experimentally testing adverse effects of real-life mixtures are scarce. In this study, we aimed at evaluating an epidemiologically identified EDC mixture in an experi-mental setting to delineate its cellular and epigenetic effects. The mixture was established using data from Swedish Environmental Longitudinal Mother and child Asthma and allergy (SELMA) study where it was associated with lower birth weight, an early marker for prenatal metabolic programming. This mixture was then tested for its ability to change metabolic programming of human mesenchymal stem cells. In these cells, we assessed if the mixture induced adipogenesis and genome-wide DNA methylation changes. The mixture increased lipid droplet accumulation already at concentrations corresponding to levels measured in the pregnant women of the SELMA study. Furthermore, we identified differentially methylated regions in genes important for adipogenesis and thermogenesis. This study shows that a mixture reflecting human real-life exposure can induce molecular and cellular changes during development that could underlie adverse outcomes.
Project description:Exposures to environmental endocrine disruptors is growing and human contact in industrialized countries has become signficant and constant. We studied the effect of chronic exposure to two endocrine disrupting compound, bisphenol A and genistein, in an in vitro cell culture system. MCF7 cells were cultured for greater than 70 passages under normal (MCF7-F) conditions or with the addition of 50 nM BPA (MCF7-B) or GEN (MCF7-G). We performed transcriptome analysis of the all three cell lines in the absence of any estrogenic compounds and in the presence of 10 nM estradiol for 3 hours.
Project description:Environmental factors such as pesticides are widely used in the agriculture of many countries and their negative impact on human health and fertility are largely unknown. There is a rapidly growing body of evidence that human reproductive health is negatively affected by the various environmental factors, including life style and exposure to the chemical compounds such as certain drugs and pesticides. Sexually reproducing organisms produce haploid gametes via a process called meiosis. Meiosis is dependent on androgen action within the testis. Pesticides and herbicides interfere with natural hormones system and are considered to be endocrine disruptors. We hypothesize that atrazine (ATZ), a herbicide used globally, adversely affects meiosis. To test this idea we used the mouse as a model organism. Mice were treated three weeks with atrazine in drinking water at concentration of 100 mg/l. To assess the molecular mechanisms of effects of ATZ on spermatogenesis we performed comparative analysis of genes expression by using Affymetrix microarray by using three biological testis samples from ATZ treated and control mice. Using a fold-change cutoff value of 1.5 and p value <0.05 (statistical Limma test (linear models test for microarray data)), we identified 51 genes that were differentially expressed in ATZ treated mice.
Project description:Environmental monitoring for pharmaceuticals and endocrine disruptors in the aquatic environment traditionally employs a variety of methods including analytical chemistry, as well as a variety of histological and biochemical endpoints that correlate with the fish fitness. It is now clear that analytical chemistry alone is insufficient to identify aquatic environments that are compromised because these measurements do not identify the biologically available dose. The biological endpoints that are measured are important because they relate to known impairments, however, they are not specific to the contaminants and often focus on only a few known endpoints. These studies can be enhanced by looking more broadly at changes in gene expression, especially if the analysis focuses on biochemical pathways. The present study was designed to obtain additional information on well-characterized sites adjacent to sewage treatment plants in MN that are thought to be impacted by endocrine disruptors. Here we examine five sites that have been previously characterized and examine changes in gene expression in fathead minnows (Pimephales promelas) that have been caged for 48 h in each of the aquatic environments. We find that the gene expression changes are characteristic and unique at each of the five sites. Also, fish exposed to two of the sites, 7 and 12, display a more aggressive behavior compared to control fish. Our results show that short-term exposure to sewage treatment plant effluents was able to induce a site-specific gene expression pattern in the fathead minnow gonad and liver. The short-term exposure was also sufficient to affect fish sexual behavior. Our results also show that microarray analysis can be very useful for determining potential exposure to chemicals, and could be used routinely as a tool for environmental monitoring.
Project description:Environmental factors during fetal development can induce a permanent epigenetic change in the germ line (sperm) that then transmits epigenetic transgenerational inheritance of adult-onset disease in the absence of any subsequent exposure. The epigenetic transgenerational actions of various environmental compounds and relevant mixtures were investigated with the use of a pesticide mixture (permethrin and insect repellant DEET), a plastic mixture (bisphenol A and phthalates), dioxin (TCDD) and a hydrocarbon mixture (jet fuel, JP8). After transient exposure of F0 gestating female rats during the period of embryonic gonadal sex determination, the subsequent F1-F3 generations were obtained in the absence of any environmental exposure. The effects on the F1, F2 and F3 generations pubertal onset and gonadal function were assessed. The plastics, dioxin and jet fuel were found to promote early-onset female puberty transgenerationally (F3 generation). Spermatogenic cell apoptosis was affected transgenerationally. Ovarian primordial follicle pool size was significantly decreased with all treatments transgenerationally. Differential DNA methylation of the F3 generation sperm promoter epigenome was examined. Differential DNA methylation regions (DMR) were identified in the sperm of all exposure lineage males and found to be consistent within a specific exposure lineage, but different between the exposures. Several genomic features of the DMR, such as low density CpG content, were identified. Exposure-specific epigenetic biomarkers were identified that may allow for the assessment of ancestral environmental exposures associated with adult onset disease. Environmental factors during fetal development can induce a permanent epigenetic change in the germ line (sperm) that then transmits epigenetic transgenerational inheritance of adult-onset disease in the absence of any subsequent exposure. The epigenetic transgenerational actions of various environmental compounds and relevant mixtures were investigated with the use of a pesticide mixture (permethrin and insect repellant DEET), a plastic mixture (bisphenol A and phthalates), dioxin (TCDD) and a hydrocarbon mixture (jet fuel, JP8). After transient exposure of F0 gestating female rats during the period of embryonic gonadal sex determination, the subsequent F1-F3 generations were obtained in the absence of any environmental exposure. The effects on the F1, F2 and F3 generations pubertal onset and gonadal function were assessed. The plastics, dioxin and jet fuel were found to promote early-onset female puberty transgenerationally (F3 generation). Spermatogenic cell apoptosis was affected transgenerationally. Ovarian primordial follicle pool size was significantly decreased with all treatments transgenerationally. Differential DNA methylation of the F3 generation sperm promoter epigenome was examined. Differential DNA methylation regions (DMR) were identified in the sperm of all exposure lineage males and found to be consistent within a specific exposure lineage, but different between the exposures. Several genomic features of the DMR, such as low density CpG content, were identified. Exposure-specific epigenetic biomarkers were identified that may allow for the assessment of ancestral environmental exposures associated with adult onset disease.
Project description:Exposures to environmental endocrine disruptors is growing and human contact in industrialized countries has become signficant and constant. We studied the effect of chronic exposure to two endocrine disrupting compound, bisphenol A and genistein, in an in vitro cell culture system. MCF7 cells were cultured for greater than 70 passages under normal (MCF7-F) conditions or with the addition of 50 nM BPA (MCF7-B) or GEN (MCF7-G). We performed transcriptome analysis of the all three cell lines in the absence of any estrogenic compounds and in the presence of 10 nM estradiol for 3 hours. The MCF7-F, B, G cell lines were starved of all estrogenic compounds by culturing the cells for 72 hours in phenol red free DMEM containing 5% charcoal/dextran treated FBS. Cells were then treated with either ethanol vehicle or 10 nM 17b-estradiol for 3 hours. Total RNA was harvested and utilized for whole genome analysis on the Affymetrix Human Trascriptome Array 2.0. The experiment was performed in duplicate