Project description:Per- and polyfluoroalkyl substances (PFAS) are environmental contaminants of concern due to their persistence and potential adverse health effects. Epidemiological studies have linked PFAS with an increased risk of uterine diseases including fibroids however, the mechanisms involved remain to be elucidated. This study investigated the effects of individual PFAS, including long-chain “legacy” PFAS [perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS)] and short-chain “alternative” PFAS compounds [undecafluoro-2-methyl-3-oxahexanoic acid (GENX/HFPO-DA), perfluorobutanesulfonic acid (PFBS)], as well as a mixture of these chemicals on the function and transcriptome of an immortalized human myometrial cell line (UT-TERT). UT-TERT cells exposed to individual PFAS displayed increased cell viability and proliferation. Flow cytometry analysis revealed that PFOS and the PFAS mixture altered cell cycle progression. Migration assays demonstrated that PFOS and the PFAS mixture significantly enhanced UT-TERT cell migration. Gap junction intercellular communication (GJIC) was impaired following PFOA, PFBS, and PFAS mixture exposure, indicating potential disruptions in cell-to-cell communication within the uterine environment. Transcriptomic analysis using RNA-seq identified substantial changes in gene expression after exposure to environmentally relevant levels of individual PFAS and PFAS mixture. Pathway analysis revealed common molecular pathways associated with PFAS exposure, including Cell-to-Cell Signaling, Lipid Metabolism, and Cell Death and Survival, while other pathways were unique to specific PFAS. These findings highlight the multifaceted effects of PFAS on myometrial cells, providing insights into the potential mechanisms underlying PFAS-associated health risks. Further research is necessary to elucidate the long-term implications of PFAS exposure on uterine function and overall reproductive health.
Project description:Per- and polyfluoroalkyl substances (PFAS) are some of the most prominent organic contaminants in human blood that have the potential to disrupt biological processes and pathways in the liver. Although the toxicological implications from human exposure to perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are well established, data on other, lesser-understood PFAS are limited. A challenge for regulatory authorities is to determine acceptable levels of human exposure to large, diverse classes of environmental contaminants. New approach methodologies (NAMs) that apply bioinformatics tools to interpret biological data are being increasingly considered to inform risk assessment when traditional toxicology methodologies are not amenable. The aim of the current investigation was to identify the biological responses relevant to PFAS mode of action as the concentration (benchmark dose) that these effects take place in order to utililze this information to inform/facilitate read-across for risk assessment of data-poor PFAS. A TempO-Seq platform (BioSpyder) measured gene expression changes in human liver microtissues (i.e., spheroids) after 1-day and 10-day exposures to increasing concentrations of PFAS. A bioinformatics framework was applied to 23 PFAS sub-classed into carboxylates (PFCAs), sulfonates (PFSAs), or PFAS precursors that were analyzed for the total altered transcripts, the concentration where effects take place, and identifying target genes of interest. Both PFCAs and PFSAs exhibited a trend toward increased transcriptional changes with carbon chain-length. Specifically, longer-chain compounds (7 to 10 carbons) were more likely to surpass liver-toxic transcriptomic thresholds established from previous studies than shorter chain PFAS. Longer-chain PFAS were also more potent, inducing transcriptional effects at lower concentrations. However, PFOS was the most potent PFAS and of all precursors, only PFOSA (a PFOS precursor) induced a response. The combined high-throughput transcriptomic and bioinformatics analyses revealed the capability of NAMs to assess the effects of PFAS in liver microtissues; such data improves our understanding of PFAS-related effects in humans and facilitates the use of read-across in human health risk assessment for other data-poor chemicals.
Project description:Using mouse lungs from perfluorooctanoic acid (PFOA) exposed mice, we examine effects of exposure to short and long chain PFAS alone or in a mixture on NLRP3 inflammasome activation and cytokine productions.
Project description:Perfluoroalkyl substances (PFAS) are a group of synthetic chemicals that are resistant to biodegradation and are environmentally persistent. PFAS are found in many consumer products including non-stick cookware, food packaging materials, upholstery, and personal care products. Accordingly, PFAS are a major source of water and soil contamination. Although use of many PFAS have been phased out, they continue to be detected in human and animal fluids, including human follicular fluid. This study investigated the effects of an environmentally relevant PFAS mixture [perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS)] on the transcriptome and function of human granulosa cells (hGCs). PFOA, PFOS, and PFHxS were detected in 100% of follicle fluid samples. Increased cell proliferation was observed in hGCs treated with the PFAS mixture with no impacts on cellular apoptosis. The PFAS mixture also altered steroid hormone synthesis, increasing both FSH-stimulated and basal progesterone secretion and concomitant upregulation of STAR protein. RNA sequencing revealed inherent differences in transcriptomic profiles in hGCs after PFAS exposure. This study demonstrates functional and transcriptomic changes in hGCs after exposure to a PFAS mixture, improving our knowledge about the impacts of PFAS exposures and female reproductive health. These findings suggest that PFAS compounds have the potential to disrupt normal granulosa cell function with possible long-term consequences on overall reproductive health.
Project description:Traditional toxicity testing has been unable to keep pace with the introduction of new chemicals into commerce. Consequently, there are limited or no toxicity data upon which to base a risk assessment for many chemicals to which fish and wildlife may be exposed. Per- and polyfluoroalkyl substances (PFAS) are emblematic of this issue in that most the ecological hazards of most PFAS remain uncharacterized. The present study employed a high throughput assay to identify the concentration at which 20 PFAS, with diverse properties, elicited a concerted gene expression response in larval fathead minnows (Pimephales promelas, 5-6 days post-fertilization) exposed for 24 h. Based on a reduced transcriptome approach that measured whole body expression of 1832 genes, the median transcriptomic point of departure (tPOD) for the 20 PFAS tested was 10 µM. Longer chain carboxylic acids (12-13 C-F) and an eight C-F di-alcohol, N-alkyl sulfonamide, and telomer sulfonic acid were among the most potent PFAS, eliciting gene expression responses at concentrations below 1 µM. With a few exceptions, larval fathead minnow tPODs were concordant with those based on whole transcriptome response in human cell lines. However, larval fathead minnow tPODs were often greater than those for Daphnia magna exposed to the same PFAS. The tPODs overlapped concentrations at which other sub-lethal effects have been reported in fish (available for 10 PFAS; including a range of species, life stages, and study designs). Nonetheless, fathead minnow tPODs were all orders of magnitude higher than aqueous PFAS concentrations detected in tributaries of the North American Great Lakes suggesting a substantial margin of safety in those systems, even for PFAS with significant potential for bioaccumulation. Overall, results broadly support the use of a fathead minnow larval transcriptomics assay to derive screening level potency estimates for use in ecological risk-based prioritization. Traditional toxicity testing has been unable to keep pace with the introduction of new chemicals into commerce. Consequently, there are limited or no toxicity data upon which to base a risk assessment for many chemicals to which fish and wildlife may be exposed. Per- and polyfluoroalkyl substances (PFAS) are emblematic of this issue in that most the ecological hazards of most PFAS remain uncharacterized. The present study employed a high throughput assay to identify the concentration at which 20 PFAS, with diverse properties, elicited a concerted gene expression response in larval fathead minnows (Pimephales promelas, 5-6 days post-fertilization) exposed for 24 h. Based on a reduced transcriptome approach that measured whole body expression of 1832 genes, the median transcriptomic point of departure (tPOD) for the 20 PFAS tested was 10 µM. Longer chain carboxylic acids (12-13 C-F) and an eight C-F di-alcohol, N-alkyl sulfonamide, and telomer sulfonic acid were among the most potent PFAS, eliciting gene expression responses at concentrations below 1 µM. With a few exceptions, larval fathead minnow tPODs were concordant with those based on whole transcriptome response in human cell lines. However, larval fathead minnow tPODs were often greater than those for Daphnia magna exposed to the same PFAS. The tPODs overlapped concentrations at which other sub-lethal effects have been reported in fish (available for 10 PFAS; including a range of species, life stages, and study designs). Nonetheless, fathead minnow tPODs were all orders of magnitude higher than aqueous PFAS concentrations detected in tributaries of the North American Great Lakes suggesting a substantial margin of safety in those systems, even for PFAS with significant potential for bioaccumulation. Overall, results broadly support the use of a fathead minnow larval transcriptomics assay to derive screening level potency estimates for use in ecological risk-based prioritization.
Project description:Data used in the creation of the Baker Lab PFAS LC-IMS-MS Skyline Library as of 10/2024. Includes reversed-phase liquid chromatography retention times, collision cross section (CCS) values, and m/z ratios for 174 PFAS and their resulting 280 ion types in positive and negative modes with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources. To use, please select the sheet which most accurately reflects your ionization method and mode, then copy and paste columns B-G, including column headers listed in row 4.