Project description:Phthalates are known endocrine disrupting chemicals and ovarian toxicants that are used widely in consumer products. Phthalates have been shown to exert ovarian toxicity on multiple endpoints, altering transcription of genes responsible for normal ovarian function. However, the molecular mechanisms by which phthalates act on the ovary are not well understood. In this study, we hypothesized that phthalates specifically target granulosa cells within the ovarian follicle. To test our hypothesis, we cultured whole mouse antral follicles for 96 hours in the presence of vehicle or 10 ug/mL of a phthalate metabolite mixture. At the end of the culture period, follicles were dissociated into single cell suspensions and subjected to single cell RNA sequencing. We used markers from published studies to identify major cell type clusters, the largest of which were granulosa and theca/stroma cells. We further identified sub-populations of granulosa, theca, and stromal cells and analyzed differentially expressed genes between the phthalate treatment and control. Granulosa cells, specifically mural granulosa cells, had the most differentially expressed genes. Pathway analysis of differentially expressed genes from the overall granulosa cell cluster revealed disruption of cell cycle and mitosis, whereas pathway analysis of the mural granola cell subcluster identified terms related to translation and ribosome. Our findings suggest that phthalates have both broad impacts on major cell types and specific impacts on individual cell types, emphasizing the complexity of phthalate toxicity and highlighting how bulk sequencing can mask effects on vulnerable cell types.
2025-01-06 | GSE277115 | GEO
Project description:Phthalate mixtures toxicity in mouse granulosa cells
Project description:Single cell RNA-seq (scRNA-seq) from Trim28 ovary knockout and wildtype mice ovaries and testis to help elucidate the function of Trim28 in the adult mouse ovaries. The analysis revealed that loss of Trim28 in the adult mouse ovaries lead to a transcriptional repogramming of the Granulosa cells towards the Sertoli cell fate. Therefore, Trim28 has a function to maintain the adult ovarian cell identity
Project description:FOXL2 is a transcription factor essential for female fertility, expressed in somatic cells of the ovary, notably granulosa cells. In the mouse, Foxl2 deletion leads to partial sex reversal postnatally. However, deletion of the gene in 8-week-old females leads to granulosa to Sertoli cell transdifferentiation. We hypothesised that different outcomes of Foxl2 deletion in embryonic versus adult ovary may depend on a different role played across ovarian development. Therefore, we characterised the dynamics of gene expression and chromatin accessibility changes in purified murine granulosa cells across key developmental stages (E14.5, 1 and 8 weeks). We then performed genome-wide identification of FOXL2 target genes and on-chromatin interacting partners by ChIP-SICAP. We found that FOXL2 regulates more genes at postnatal stages, through the interaction with factors regulating primordial follicle activation (PFA), such as NR5A2, and others regulating steroidogenesis including AR and ESR2. As a proof of principle experiment, we chose one FOXL2 interactor, Ubiquitin specific protease 7 (USP7) and showed that deletion of this gene in granulosa cells leads to a blockage of PFA, impaired ovary development and sterility. Our study constitutes a comprehensive resource for exploration of the molecular mechanisms of ovarian development and causes of female infertility.
Project description:We report the results of an RNA-seq analysis conducted as part of an experiment investigating the effects of the phthalate, mono-(2-ethylhexyl) phthalate (MEHP), and all-trans retinoic acid (ATRA) on cultured fetal mouse testes. The goal of the study was to determine whether fetal testis toxicity of MEHP is partially driven by disruption of retinoic acid signaling.
Project description:Luteinizing hormone (LH) activation of the EGF receptor/RAS/ERK1/2 pathway is essential for ovulation and luteinization because granulosa cell depletion of Erk1/2 (Erk1/2gc-/- mice) renders mice completely infertile. Because of their potential as mediators of ERK1/2-dependent granulosa cell differentiation, we disrupted genes encoding the CCAAT/enhancer-binding proteins, (C/EBP) a and C/EBPb. Female Cebpbgc-/- mutant mice but not Cebpagc-/- mice were subfertile whereas Cebpa/bgc-/- double mutant females were sterile. Follicles failed to ovulate, ovaries were devoid of corpora lutea, luteal cell marker genes (Lhcgr, Prlr, Ptgfr, Cyp11a1 and Star) were absent and serum progesterone levels were low. Microarray analyses identified numerous C/EBPa/b target genes in eCG-hCG treated mice. At 4h post-hCG, a subset (19%) of genes altered in the Cebpa/b depleted cells was also altered in Erk1/2 depleted cells; hence they are common effectors of ERK1/2. Additional genes down-regulated in the Cebpa/b depleted cells at 8 and 24h post-hCG include known (Akr1b7, Runx2, Star, Saa3) and novel (Abcb1b, Apln, Igfbp4, Prlr, Ptgfr Timp4) C/EBP target genes including effectors of vascular cell development. Bhmt, a gene controlling methionine metabolism and expressed exclusively in liver and kidney, was high in WT luteal cells but totally absent in Cebpa/b mutant cells. Because numerous genes potentially associated with vascular development were suppressed in the mutant cells, C/EBPa/b appear to dictate the luteinization process by also controlling genes that regulate the formation of the extensive vascular network required to sustain luteal cells. Thus, C/EBPa/b mediate several aspects of granulosa cell differentiation as well as the complex process of luteinization. Five granulosa cell treatments were included: CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 4h wild type ovary, eCG-treated 48h, hCG 8h CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 8h wild type ovary, eCG-treated 48h, hCG 24h CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 24h
Project description:Transcriptomic analysis reveals potential mechanisms of toxicity in a combined exposure to dibutyl phthalate and diisobutyl phthalate in zebrafish (Danio rerio) ovary
Project description:Phthalate esters (PAEs), a notable plasticizer, could be prolific contaminants in the aquatic environment, and have been shown to induce reproductive toxicity. However, studies concerning the toxicity towards aquatic species are based upon individual chemicals and the combined toxicity of PAEs to aquatic organisms remains unclear. The aim of this study was to explore the potential toxic mechanism of combined exposure to dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) in adult female zebrafish ovarian. Zebrafish were exposed to DBP, DiBP and their mixtures for 30 days, and their effects on ovarian histology, plasma sex hormones and ovarian transcriptomics were investigated. The plasma estradiol (E2) levels were significantly decreased 38.9% for DBP-1133 exposure group and 41.0% for DiBP-1038 exposure group. The percentages of late/mature oocyte were also significantly decreased 17.3% in DBP-1133 exposure and 16.2% in DiBP-1038 exposure, while those in combined exposure were not significantly affected. Nonetheless, transcriptome sequencing discovered 2564 differential expressed genes (DEGs) in zebrafish ovary after exposure to the mixtures. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified that those DEGs were involved in the neuroactive ligand-receptor interaction, GnRH, progesterone-mediated oocyte maturation, oocyte meiosis and steroid hormone biosynthesis signaling pathways. These results revealed that combined exposure showed potential reproductive toxicity at the molecular level.