Project description:Environmental factors during perinatal development influence developmental plasticity and disease susceptibility via alterations to the epigenome. Developmental exposure to the endocrine active compound, bisphenol A (BPA), has previously been associated with altered methylation at candidate gene loci. Here, we undertake the first genome-wide characterization of DNA methylation profiles in the liver of murine offspring perinatally exposed to multiple doses of BPA through the maternal diet. Using a tiered focusing approach, our strategy proceeds from unbiased broad DNA methylation analysis using methylation-based next generation sequencing technology to in-depth quantitative site-specific CpG methylation determination using the Sequenom EpiTYPER MassARRAY platform to profile liver DNA methylation patterns in offspring maternally exposed to BPA during gestation and lactation to doses ranging from 0 BPA/kg (Ctr), 50 M-BM-5g BPA/kg (UG), or 50 mg BPA/kg (MG) diet (N=4 per group). Genome-wide analyses indicate non-monotonic effects of DNA methylation patterns following perinatal exposure to BPA, corroborating previous studies using multiple doses of BPA with non-monotonic outcomes. We observed enrichment of regions of altered methylation (RAMs) within CpG island (CGI) shores, but little evidence of RAM enrichment in CGIs. An analysis of promoter regions identified several hundred novel BPA-associated methylation events, and methylation alterations in the Myh7b and Slc22a12 gene promoters were validated. Using the Comparative Toxicogenomics Database, a number of candidate genes that have previously been associated with BPA-related gene expression changes were identified, and gene set enrichment testing identified epigenetically dysregulated pathways involved in metabolism and stimulus response. In this study, non-monotonic dose dependent alterations in DNA methylation among BPA-exposed mouse liver samples and their relevant pathways were identified and validated. The comprehensive methylome map presented here provides candidate loci underlying the role of early BPA exposure and later in life health and disease status. For this study, liver DNA from a subset of a/a wild-type animals was analyzed for full methylome characteristics: 1) standard diet (Ctr, n = 4 offspring; 2 male and 2 female); 2) 50 M-BM-5g BPA/kg diet (UG, n = 4 offspring; 2 male and 2 female); 3) 50 mg BPA/kg diet (MG, n = 4 offspring; 1 male and 3 female).
Project description:Exposure to bisphenol A (BPA), an endocrine disruptor (ED), has raised concerns for both human and ecosystem health. Epigenetic factors, including microRNAs, are key regulators of gene expression during cancer. The effect of BPA exposure on the zebrafish epigenome remains poorly characterized. Zebrafish represents an excellent model to study cancer as the organism develops disease that resembles human cancer. Using zebrafish as systems toxicology model, we hypothesized that chronic BPA-exposure impacts the miRNome in adult zebrafish and establishes an epigenome more susceptible to cancer development. After a 3 week exposure to 100 nM BPA, RNA from the liver was extracted to perform high throughput mRNA and miRNA sequencing. Differential expression (DE) analyses comparing BPA-exposed to control specimens were performed using established bioinformatics pipelines. In the BPA-exposed liver, 6,188 mRNAs and 15 miRNAs were differently expressed (q ≤ 0.1). By analyzing human orthologs of the DE zebrafish genes, signatures associated with non-alcoholic fatty liver disease (NAFLD), oxidative phosphorylation, mitochondrial dysfunction and cell cycle were uncovered. Chronic exposure to BPA has a significant impact on the liver miRNome in adult zebrafish and has the potential to cause adverse outcomes including cancer.
Project description:Three different cell lines (MCF-7, MCF-10A, MCF-12A) were exposed to varying concentrations of BPA, BPA-analogues, pendimethalin and pendimethalin formulation.
Project description:Antibiotic adjuvants are commonly described as an alternative approach to overcome bacterial resistance towards conventional antibiotics. In this experiment, we investigated this statement for tobramycin (TOB) in combination with three adjuvants; baicalin hydrate (BH), a quorum sensing inhibitor, econazole (ECO) and miconazole (MICO), two antifungal agents that are repurposed as antibiotic adjuvants. We repeatedly exposed mature (24 hour old) Burkholderia cenocepacia J2315 biofilm cells to TOB alone (768ug/ml), or a combination of TOB with either BH (250uM), ECO (1uM) or MICO (1uM). We also included an untreated control. After a treatment, the remaining cells were quantified and the cells were allowed to regrow for another 48 hours. This process is one cycle. At the end of the experiment, biofilm cells were exposed to 15 cycles. DNA extraction was performed on the evolved cells and of cells from the start population. DNA sequencing was performed on these samples and single nucleotide polymorphisms compared to the start population were evaluated.
Project description:The endocrine disrupting chemical bisphenol A (BPA) can affect reproductive organs, tissues and cells in several species. Treatment of human endometrial endothelial cells (HEECs) with 50 µM BPA decreased their proliferation compared with the control. Microarray analyses revealed that BPA affected biological processes such as the cell cycle, cell division, and cytoskeleton organization, confirming the results of the proliferation assay. Expression of three of the most differentially expressed genes identified in the microarray analysis was verified by real-time quantitative reverse transcription polymerase chain reaction in five HEEC cultures obtained from women in the proliferative phase and in five cultures obtained from women in the secretory phase of the menstrual cycle after treatment with BPA. The present study supports our previous findings of decreased proliferation and increased cell death in response to BPA, and may offer important clues to the mechanisms of action of BPA. Keywords: Exposure analysis Two-condition experiments, BPA-exposed vs. control HEEC. Biological replicates: 5 HEEC cultures, independently grown, exposed and harvested. One replicate per array. Dye-swaps for exposed and reference samples between replicates.