Differential effect of estradiol and bisphenol A on Set8 and Sirt1 expression in prostate cancer

EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP), Lambré C, Barat Baviera JM, Bolognesi C, Chesson A, Cocconcelli PS, Crebelli R, Gott DM, Grob K, Lampi E, Mengelers M, Mortensen A, Rivière G, Silano (until 21 December 2020†) V, Steffensen I, Tlustos C, Vernis L, Zorn H, Batke M, Bignami M, Corsini E, FitzGerald R, Gundert‐Remy U, Halldorsson T, Hart A, Ntzani E, Scanziani E, Schroeder H, Ulbrich B, Waalkens‐Berendsen D, Woelfle D, Al Harraq Z, Baert K, Carfì M, Castoldi AF, Croera C, Van Loveren H. Re-evaluation of the risks to public health related to the presence of bisphenol A (BPA) in foodstuffs

In 2015, EFSA established a temporary tolerable daily intake (t-TDI) for BPA of 4 μg/kg body weight (bw) per day. In 2016, the European Commission mandated EFSA to re-evaluate the risks to public health from the presence of BPA in foodstuffs and to establish a tolerable daily intake (TDI). For this re-evaluation, a pre-established protocol was used that had undergone public consultation. The CEP Panel concluded that it is Unlikely to Very Unlikely that BPA presents a genotoxic hazard through a direct mechanism. Taking into consideration the evidence from animal data and support from human observational studies, the immune system was identified as most sensitive to BPA exposure. An effect on Th17 cells in mice was identified as the critical effect; these cells are pivotal in cellular immune mechanisms and involved in the development of inflammatory conditions, including autoimmunity and lung inflammation. A reference point (RP) of 8.2 ng/kg bw per day, expressed as human equivalent dose, was identified for the critical effect. Uncertainty analysis assessed a probability of 57-73% that the lowest estimated Benchmark Dose (BMD) for other health effects was below the RP based on Th17 cells. In view of this, the CEP Panel judged that an additional uncertainty factor (UF) of 2 was needed for establishing the TDI. Applying an overall UF of 50 to the RP, a TDI of 0.2 ng BPA/kg bw per day was established. Comparison of this TDI with the dietary exposure estimates from the 2015 EFSA opinion showed that both the mean and the 95th percentile dietary exposures in all age groups exceeded the TDI by two to three orders of magnitude. Even considering the uncertainty in the exposure assessment, the exceedance being so large, the CEP Panel concluded that there is a health concern from dietary BPA exposure.

Comprehensive analysis based in silico study of alternative bisphenols - Environmental explanation of prostate cancer progression

Industries have begun to shift their focus on exploring substitute chemicals for BPA due to their concerns about safety and environmental pollution. In recent years, alternative bisphenols, including BPS, BPF, and BPAF have been extensively used as BPA substitutes. Based on previous studies, BPA is considered a risk factor for prostate cancer. This work aims to explore the interactive genes related to alternative bisphenols and prostate cancer using the TCGA, CTD, and GEO databases. After performing the GO and KEGG enrichment analysis, a correlation between alternative bisphenols and prostate cancer was detected using bioinformatics analysis. Among the interactive genes of alternative bisphenols, ferroptosis-related genes revealed strong correlations with prostate cancer. Moreover, the prognostic predictive model, ROC curve, and survival analysis confirmed that ferroptosis-related genes displayed a strong correlation in the prognosis of prostate cancer. We successfully evaluated the relationship between prostate cancer and alternative bisphenols; as a result, a novel approach was proposed to explore the damaging effect of environmental endocrine disruptors.

Effects of androgens and estrogens on sirtuin 1 gene expression in human aortic endothelial cells

Objectives:

To investigate the effect of androgens and estrogens on surtuin 1 (SIRT1) expression in human aortic endothelial cells (HAECs).

Methods:

Real-time polymerase chain reaction analysis of SIRT-1 expression over 48 hours (h) was performed in HAECs treated with various concentrations of dehydroepiandrostendione (DHEA), androstenedione and testosterone (androgens), estrone (E1), estradiol (E2), and estriol (E3) (estrogens) to investigate the dose-dependency of time courses. The influence of high glucose on SIRT1 expression induced by the androgens and estrogens was also examined.

Results:

Dehydroepiandrostendione, androstenedione, and testosterone remarkably produced a dose-dependent increase in SIRT1 expression in the range of 10 to 20 μg/ml. High glucose (40mM) medium had significantly inhibitory effects on 10 μg/ml DHEA-induced SIRT1 expression (p=0.024). Estrone and E2, but not E3, caused a marked dose-dependent increase in SIRT1 expression from 10 to 20 μg/ml. Treatment with 20 mM or 40 mM glucose medium did not significantly inhibit E1- and E3-induced SIRT1 expression in control medium; however, both high glucose mediums significantly emphasized E2-induced SIRT1 expression in control medium (p=0.007, p=0.005).

Conclusion:

These results suggest that DHEA, androstenedione, testosterone, E1, and E2 definitely activate SIRT1 expression in HAECs. A high glucose medium is potent to inhibit the basal gene expression; however, it could not reduce powerful androgen- and estrogen-induced SIRT1 expression in HAECs.

Endocrine-disrupting effects of bisphenols on urological cancers

Bisphenols are endocrine-disrupting chemicals found in a broad range of products that can modulate hormonal signalling pathways and various other biological functions. These compounds can bind steroid receptors, e.g. estrogen and androgen receptors, expressed by numerous cells and tissues, including the prostate and the bladder, with the potential to alter their homeostasis and normal physiological functions. In the past years, exposure to bisphenols was linked to cancer progression and metastasis. As such, recent pieces of evidence suggest that endocrine-disrupting chemicals can lead to the development of prostate cancer. Moreover, bisphenols are found in the urine of the wide majority of the population. They could potentially affect the bladder's normal physiology and cancer development, even if the bladder is not recognized as a hormone-sensitive tissue. This review will focus on prostate and bladder malignancies, two urological cancers that share standard carcinogenic processes. The description of the underlying mechanisms involved in cell toxicity, and the possible roles of bisphenols in the development of prostate and bladder cancer, could help establish the putative roles of bisphenols on public health.

Genome-Wide Analysis of Low Dose Bisphenol-A (BPA) Exposure in Human Prostate Cells

Endocrine disrupting compounds (EDCs) have the potential to cause adverse effects on wild-life and human health. Two important EDCs are the synthetic estrogen 17α-ethynylestradiol (EE2) and bisphenol-A (BPA) both of which are xenoestrogens (XEs) as they bind the estrogen receptor and dis-rupt estrogen physiology in mammals and other vertebrates. In the recent years the influence of XEs on oncogenes, specifically in relation to breast and prostate cancer has been the subject of considerable study.

Mono-(2-ethylhexyl) Phthalate Aggravates Inflammatory Response via Sirtuin Regulation and Inflammasome Activation in RAW 264.7 Cells

Artificial environmental endocrine disrupting chemicals (EDCs) exert public health concerns. Exposure to EDCs may induce various disorders in the cardiometabolic system. However, the underlying mechanisms remain largely unknown. Over the past decade, an abundance of evidence has emerged demonstrating a close link between cardiometabolic disorders and inflammation. The aim of the present study was to evaluate the immunological effects on macrophages from six EDCs via sirtuin (SIRT) regulation using the murine macrophage RAW 264.7 cell. We studied first the effects of these EDCs, including a series of doses of benzyl butyl phthalate (BBP), bisphenol A (BPA), diethylhexyl phthalate (DEHP), mono-(2-ethylhexyl)phthalate (MEHP), perfluorooctanoate (PFOA), or perfluorooctanesulfonate (PFOS), on SIRT1-7 transcriptional level. Among these EDCs, MEHP significantly decreased all sirtuin genes' expression in a dose-dependent manner. Under MEHP treatment, SIRT activity and protein expression were significantly decreased, while the protein expression of acetylated NF-κB was significantly increased along with significant increases in IL-1β transcription. These results indicate that MEHP may induce the inflammatory response via SIRT-mediated acetylation of NF-κB. Additionally, the enhanced IL-1β secretion in the presence of 50 μM MEHP ( P < 0.01) also supports inflammasome activation (significant ASC and NLRP3 protein augmentation). Both events may be regulated by MEHP induced reactive oxygen species ( P < 0.01). In conclusion, our study suggests for the first time that EDCs differentially modulate sirtuins' gene expression levels in macrophages and that a specific phthalate MEHP can lead to an increased inflammatory response by impairing vital epigenetic regulators and inflammasome activation.

Differential Effects of Estradiol and Bisphenol A on SET8 and SIRT1 Expression in Ovarian Cancer Cells

Exposure to estrogenic compounds has been shown to epigenetically reprogram the female reproductive tract and may contribute to ovarian cancer. The goal of this study was to compare the effect of estradiol or bisphenol A (BPA) on the expression of histone-modifying enzymes (HMEs) in ovarian cancer cells. Using 2 human ovarian cancer cell lines, we examined the expression of SET8, a histone methyltransferase, and SIRT1, a histone deacetylase, after exposure to estrogen or BPA. These experiments were carried out in complete media (fetal bovine serum) that contain natural hormones to understand the impact of additional exposure to estrogen or BPA on HME expression. We found differential expression of the HMEs in the different models examined and between the different compounds. Further, we determined that the changes in gene expression occurred via estrogen receptor signaling using the estrogen receptor antagonist, ICI 182,780 (fulvestrant).