Concentrations of 11 PFASs were determined in muscle and whole fish for six species collected from Charleston, South Carolina (SC) for the assessment of potential health risks to humans and wildlife. Across all species and capture locations, total PFAS levels in whole fish were significantly higher than fillets by a factor of two- to three-fold. Mean ∑PFAS concentrations varied from 12.7 to 33.0 ng/g wet weight (ww) in whole fish and 6.2-12.7 ng/g ww in fillets. For individual whole fish, ∑PFASs ranged from 12.7 ng/g ww in striped mullet to 85.4 ng/g ww in spotted seatrout, and in fillets individual values ranged from 6.2 ng/g ww in striped mullet to 27.9 ng/g ww in spot. The most abundant compound in each species was perfluorooctane sulfonate (PFOS), comprising 25.5-69.6% of the ∑PFASs. Striped mullet had significantly lower relative amounts of PFOS compared to all other species and higher relative amounts of PFUnDA compared to Atlantic croaker, spotted seatrout, and spot. Unlike whole fish, PFAS levels in fillets varied significantly by location with higher ∑PFOS from the Ashley River than the Cooper River and Charleston Harbor, which reflects the levels of PFASs contamination in these systems. In whole fish, differences in relative concentrations of PFOS, PFNA, and PFDA occurred by capture location, suggestive of different sources. PFOS concentrations for southern flounder and spotted seatrout fillets were within the advisory range to limit fish consumption to 4 meals a month. PFOS levels exceeded screening values to protect mammals in 83% of whole fish examined and represent a potential risk to wildlife predators such as dolphins.
Phthalates are known endocrine disruptors and associated with decreased fecundity, pregnancy loss, and adverse obstetrical outcomes, however the underlying mechanisms remain to be established. Environmental factors can influence gene expression and cell function by modifying epigenetic marks, impacting the developing embryo as well as future generations of offspring. The impact of phthalates on placental gene methylation and expression is largely unknown. We studied the effect of maternal phthalate exposure on the human placental DNA methylome and transcriptome. We determined epigenome-wide DNA methylation marks (Illumina Infinium Human Methylation 850k BeadChip) and gene expression (Agilent whole human genome array) associated with phthalate exposure in first trimester placenta. Integrative genomic analysis of candidate genes was performed to define gene methylation-expression relationships. We identified 39 genes with significantly altered methylation and gene expression in the high phthalate exposure group. Most of these relationships were inversely correlated. This analysis identified epidermal growth factor receptor (EGFR) as a critical candidate gene mediating the effects of phthalates on early placental function. Although additional studies are needed to determine the functional consequences of these changes, our findings are consistent with the model that phthalates impact placental function by modulating the expression of critical placental genes through epigenetic regulation.
Background: The health effects of bisphenol A (BPA) and di-(2-ethylhexyl) phthalate (DEHP) have been studied extensively in children. The impact of other chemicals in these two classes has not been investigated as fully. Methods: We conducted a cross-sectional pilot study of 10–13 y old healthy children. We assessed descriptive, univariable, and multivariable associations of urinary metabolites of bisphenols and phthalates with oxidant stress, insulin resistance, body mass, and endothelial dysfunction. Possible associations with brachial artery distensibility, pulse wave velocity (markers of vascular stiffness), and serum endothelial cell-derived microparticle levels were also assessed. Results: We enrolled 41 participants, 12.1 ± 1.0 y, most of whom were Mexican Americans (42%) or other Hispanics (34%). Increased BPA levels were associated with increased levels of F2-isoprostane (ng/ml) (P = 0.02), with a similar trend for DEHP metabolites. Each log unit increase of high molecular weight (HMW) phthalate metabolites was associated with a 0.550 increase in Homeostatic Model Assessment of insulin resistance (HOMA-IR) units (P = 0.019) and altered circulating levels of activated endothelial cell-derived microparticles (% per ml) (P = 0.026). Bisphenol S (BPS), a replacement for BPA, was associated with increased albumin (mg):creatinine (g) ratio (P = 0.04). Metabolites of HMW phthalates were also associated with decreased brachial artery distensibility (P = 0.047). Conclusion: Exposure to bisphenols and phthalates, including a BPA replacement, is associated with increased oxidant stress, insulin resistance, albuminuria, as well as disturbances in vascular function in healthy children.
Although the anti-cancer effects of curcumin has been shown in various cancer cell types, in vitro, pre-clinical and clinical studies showed only a limited efficacy, even at high doses. This is presumably due to low bioavailability in both plasma and tissues, particularly due to poor intracellular accumulation. A variety of methods have been developed to achieve the selective targeting of drugs to cells and mitochondrion. We used a novel approach by conjugation of curcumin to lipophilic triphenylphosphonium (TPP) cation to facilitate delivery of curcumin to mitochondria. TPP is selectively taken up by mitochondria driven by the membrane potential by several hundred folds. In this study, three mitocurcuminoids (mitocurcuminoids-1, 2, and 3) were successfully synthesized by tagging TPP to curcumin at different positions. ESI-MS analysis showed significantly higher uptake of the mitocurcuminoids in mitochondria as compared to curcumin in MCF-7 breast cancer cells. All three mitocurcuminoids exhibited significant cytotoxicity to MCF-7, MDA-MB-231, SKNSH, DU-145, and HeLa cancer cells with minimal effect on normal mammary epithelial cells (MCF-10A). The IC50 was much lower for mitocurcuminoids when compared to curcumin. The mitocurcuminoids induced significant ROS generation, a drop in ΔØm, cell-cycle arrest and apoptosis. They inhibited Akt and STAT3 phosphorylation and increased ERK phosphorylation. Mitocurcuminoids also showed upregulation of pro-apoptotic BNIP3 expression. In conclusion, the results of this study indicated that mitocurcuminoids show substantial promise for further development as a potential agent for the treatment of various cancers.
1 September 2017 in Science of The Total Environment