Development of a Biosensor Platform for Phenolic Compounds Using a Transition Ligand Strategy.

The time-consuming and laborious characterization of protein or microbial strain designs limits the development of high-performance biocatalysts for biotechnological applications. Here, transcriptional biosensors emerged as valuable tools as they allow for rapid characterization of several thousand variants within a very short time. However, for many molecules of interest, no specific transcriptional regulator determining a biosensor's specificity is available. We present an approach for rapidly engineering biosensor specificities using a semirational transition ligand approach combined with fluorescence-activated cell sorting. In this two-step approach, a biosensor is first evolved toward a more relaxed-ligand specificity before using the resulting variant as the starting point in a second round of directed evolution toward high specificity for several chemically different ligands. By following this strategy, highly specific biosensors for 4-hydroxybenzoic acid, p-coumaric acid, 5-bromoferulic acid, and 6-methyl salicylic acid were developed, starting from a biosensor for the intracellular detection of trans-cinnamic acid.

Oleacein inhibits STAT3, activates the apoptotic machinery, and exerts anti-metastatic effects in the SH-SY5Y human neuroblastoma cells.

Several studies published in the last decade suggest that the beneficial role of extra-virgin olive oil (EVOO) in human health is mostly attributable to the main secoiridoid derivatives (oleuropein, oleocanthal, and oleacein). Anti-cancer properties have also been demonstrated for certain compounds present in small quantities in EVOO, including oleuropein and hydroxytyrosol, which have been extensively studied, while minor attention has been given to the most abundant secoiridoid oleacein. The aim of our research was to study the molecular mechanisms underlying the anti-proliferative and anti-metastatic capacity of oleacein in the SH-SY5Y human neuroblastoma cell line. Our results demonstrate that oleacein is able to reduce the proliferation of the SH-SY5Y cells by blocking the cell cycle in the S phase and inducing apoptotic cell death through the increase in both Bax and p53 as well as a reduction in the Bcl-2 expression and STAT3 phosphorylation. Moreover, oleacein caused reduction in the SH-SY5Y cell adhesion and migration. Overall, these findings indicate that oleacein exerts anti-cancer effects against neuroblastoma cells, suggesting a promising role as a candidate against this type of cancer.

Bisphenol S Impaired In Vitro Ovine Early Developmental Oocyte Competence.

INTRODUCTION: Bisphenol A (BPA) is a widespread compound in the plastic industry that is especially used to produce baby bottles, food packaging and metal cans. BPA, an endocrine disruptor, leads to alterations in reproductive function and therefore has been banned from the food industry. Unregulated BPA analogues, particularly Bisphenol S (BPS), have emerged and are now used in the plastic industry. Thus, this study aimed to examine the acute effects of low and environmental doses of BPS on ewe oocyte quality and developmental competence, and its mechanism of action, during in vitro maturation. METHODS: Ewe cumulus-oocyte complexes underwent in vitro maturation in the presence or absence of BPS (1 nM, 10 nM, 100 nM, 1 µM or 10 µM). Oocytes were then subjected to in vitro fertilisation and development. RESULTS: 1 µM BPS induced a 12.7% decrease in the cleavage rate (p = 0.004) and a 42.6% decrease in the blastocyst rate (p = 0.017) compared to control. The blastocyst rate reduction was also observed with 10 nM BPS. Furthermore, 10 µM BPS reduced the oocyte maturation rate, and 1 µM BPS decreased cumulus cell progesterone secretion. PR and AMH gene expression were reduced in cumulus cells. BPS induced a 5-fold increase in MAPK 3/1 activation (p = 0.04). CONCLUSIONS: BPS impaired ewe oocyte developmental competence. The data suggest that BPS might not be a safe BPA analogue. Further studies are required to elucidate its detailed mechanism of action.

The inhibition of heme oxigenase-1 (HO-1) abolishes the mitochondrial protection induced by sesamol in LPS-treated RAW 264.7 cells.

Redox impairment and mitochondrial dysfunction have been seen in inflammation. Thus, there is interest in studies aiming to find molecules that would exert mitochondrial protection in mammalian tissues undergoing inflammation. Sesamol (SES) is an antioxidant and anti-inflammatory molecule as demonstrated in both in vitro and in vivo experimental models. Nonetheless, it was not previously demonstrated whether and how SES would cause mitochondrial protection during inflammation. Thus, we investigated here whether a pretreatment (for 1 h) with SES (1-100 µM) would prevent mitochondrial impairment in lipopolysaccharide (LPS)-treated RAW 264.7 cells. It was also evaluated whether the heme oxigenase-1 (HO-1) would be involved in the effects on mitochondria induced by SES. We found that SES reduced the levels of lipid peroxidation and protein nitration in the membranes of mitochondria obtained from LPS-treated RAW 264.7 cells. SES also attenuated the production of superoxide anion radical (O2-•) and nitric oxide (NO•) in this experimental model. SES suppressed the LPS-elicited mitochondrial dysfunction, as assessed through the analyses of the activities of the mitochondrial complexes I and V. SES also abrogated the LPS-induced decrease in the levels of adenosine triphosphate (ATP) and in the mitochondrial membrane potential (MMP). SES induced mitochondria-related anti-apoptotic effects in LPS-treated cells. Besides, SES pretreatment abrogated the LPS-triggered inflammation by decreasing the levels of pro-inflammatory proteins. The SES-induced mitochondria-associated protection was blocked by the specific inhibitor of HO-1, ZnPP IX (20 µM). Therefore, SES induced mitochondrial protection in LPS-treated cells by a mechanism involving HO-1.

Effects of bisphenol A (BPA) on brain-specific expression of cyp19a1b gene in swim-up fry of Labeo rohita.

Estrogen regulates numerous developmental and physiological processes and effects are mediated mainly by estrogenic receptors (ERs), which function as ligand-regulated transcription factor. ERs can be activated by many different types endocrine disrupting chemicals (EDCs) and interfere with behaviour and reproductive potential of living organism. Estrogenic regulation of membrane associated G protein-coupled estrogen receptor, GPER activity has also been reported. Bisphenol A (BPA), a ubiquitous endocrine disruptor is present in many household products, has been linked to many adverse effect on sexual development and reproductive potential of wild life species. The present work is aimed to elucidate how an environmentally pervasive chemical BPA affects in vivo expression of a known estrogen target gene, cyp19a1b in the brain, and a known estrogenic biomarker, vitellogenin (Vg) in the whole body homogenate of 30 days post fertilization (dpf) swim-up fry of Labeo rohita. We confirm that, like estrogen, the xenoestrogen BPA exposure for 5-15 days induces strong overexpression of cyp19a1b, but not cyp19a1a mRNA in the brain and increase concentration of vitellogenin in swim-up fry. BPA also induces strong overexpression of aromatase B protein and aromatase activity in brain. Experiments using selective modulators of classical ERs and GPER argue that this induction is largely through nuclear ERs, not through GPER. Thus, BPA has the potential to elevate the levels of aromatase and thereby, levels of endogenous estrogen in developing brain. These results indicate that L. rohita swim-up fry can be used to detect environmental endocrine disruptors either using cyp19a1b gene expression or vitellogenin induction.

Toxicity evaluation of lignocellulose-derived phenolic inhibitors on Saccharomyces cerevisiae growth by using the QSTR method.

Quantitative Structure-toxicity Relationship (QSTR) models were built to evaluate the toxicity of lignocellulose-derived phenolic inhibitors on the growth of Saccharomyces cerevisiae in a bioethanol production process. The established models were proved to be reliable after rigorous validation and showed values of R2 > 0.6 and Q2LOO > 0.5. They could provide accurate guidance for alleviating the most toxic inhibitors in pretreated lignocellulosic hydrolysates, thus facilitating bioethanol production. The results showed that the inhibitors that possessed unsaturated bonds, formyl groups and carbonyl group substituents showed obvious toxicity effects. The toxicity of the inhibitors with ortho-electron-withdrawing substituents was stronger than that of metra- or para-electron-donating substituents. Ferulic acid was chosen to analyze its toxicity in practical alkali-pretreated rice straw hydrolysates because of its strong toxicity and high concentration. The results showed that its toxicity was up to 82%, which was suggested to be dominantly detoxified in the bioethanol production process.

Healing potential of Adiantum capillus-veneris L. plant extract on bisphenol A-induced hepatic toxicity in male albino rats.

Bisphenol A (BPA) is a widely used environmental pollutant in the production of plastics but causes hepatotoxicity in mammals. In the present study, we studied the BPA-induced oxidative stress in rats and ameliorative potential of Adiantum capillus-veneris L. plant. It was concluded that the BPA can reduce the body and liver weight, increase in biochemical levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total bilirubin, and disturb the normal hepatic physiology, histology, and metabolism. Additionally, liver histology shows hepatic necrosis, congestion, and vacuolization in exposed individuals. In contrast, simultaneous exposure of A. capillus-veneris and BPA showed declining trend in serum biomarker levels and normal histopathological structures. We conclude that the A. capillus-veneris plant is antioxidant in nature and can reduce the BPA-induced toxicity. These findings are very helpful to understand the BPA-induced hepatic toxicity and ameliorative potential of A. capillus-veneris plant and are of great importance in risk assessment of xenobiotics.

Inhibitory activity of phenolic-rich pistachio green hull extract-enriched pasta on key type 2 diabetes relevant enzymes and glycemic index.

Phenolic compounds as agro-industrial by-products have been associated with health benefits since they exhibit high antioxidant activity and anti-diabetic properties. In this study, polyphenol-rich extract from pistachio green hull (PGH) was evaluated for antioxidant activity and its ability to inhibit α-amylase and α-glucosidase activity in vitro. The effect of PGH extract powder on in vitro starch digestibility was also evaluated. The results showed that PGH had stronger antioxidant activity than Trolox. The inhibitory effect of PGH extract against α-amylase from porcine pancreas was dose dependent and the IC50 value was ~174µgGAE/mL. The crude PGH extract was eight times more potent on baker yeast α-glucosidase activity (IC50~6µgGAE/mL) when compared to acarbose, whereas the IC50 value of PGH extract against rat intestinal maltase activity obtained ~2.6mgGAE/mL. The non-tannin fraction of PGH extract was more effective against α-glucosidase than tannin fraction whereas the α-amylase inhibitor was concentrated in the tannin fraction. In vitro starch digestibility and glycemic index (GI) of pasta sample supplemented with PGH extract powder (1.5%) was significantly lower than the control pasta. The IC50 value of PGH extract obtained from cooked pasta against α-amylase and α-glucosidase was increased. These results have important implications for the processing of PGH for food industry application and therefore could comply with glucose control diets.

Involvement of Insulin Signaling Disturbances in Bisphenol A-Induced Alzheimer's Disease-like Neurotoxicity.

Bisphenol A (BPA), a member of the environmental endocrine disruptors (EDCs), has recently received increased attention because of its effects on brain insulin resistance. Available data have indicated that brain insulin resistance may contribute to neurodegenerative diseases. However, the associated mechanisms that underlie BPA-induced brain-related outcomes remain largely unknown. In the present study, we identified significant insulin signaling disturbances in the SH-SY5Y cell line that were mediated by BPA, including the inhibition of physiological p-IR Tyr1355 tyrosine, p-IRS1 tyrosine 896, p-AKT serine 473 and p-GSK3α/ß serine 21/9 phosphorylation, as well as the enhancement of IRS1 Ser307 phosphorylation; these effects were clearly attenuated by insulin and rosiglitazone. Intriguingly, Alzheimer's disease (AD)-associated pathological proteins, such as BACE-1, APP, ß-CTF, α-CTF, Aß 1-42 and phosphorylated tau proteins (S199, S396, T205, S214 and S404), were substantially increased after BPA exposure, and these effects were abrogated by insulin and rosiglitazone treatment; these findings underscore the specific roles of insulin signaling in BPA-mediated AD-like neurotoxicity. Thus, an understanding of the regulation of insulin signaling may provide novel insights into potential therapeutic targets for BPA-mediated AD-like neurotoxicity.

Pharmacological Analysis of the Therapeutic Effect of Radioprotectors Cystamine and Indralin in the Capacity of Radiomitigators.

The therapeutic radiomitigating effect of cystamine and indralin was studied in experiments on mice and rats and pharmacological analysis of these drugs was carried out. The animals were subjected to whole-body 60Co γ-irradiation. The mice were exposed to single (9-10 Gy) or double (8 Gy) irradiation with an interval of 1 month. The rats were exposed to 10 Gy with partial shielding of the upper quarter of the abdomen. In experiments on mice, pretreatment with reserpine abolished the therapeutic effect of cystamine administered repeatedly every 15 min over 1 h after irradiation. Moreover, summation of the radioprotective and therapeutic effects of the radioprotector was revealed under these conditions. In mice and rats, α1-adrenoreceptor blocker terazosin did not abolish the therapeutic effect of indralin administrated after irradiation, but blocked the radioprotective effect of indralin applied prior to irradiation. At the same time, 5-HT2 serotonin receptor blocker tropoxin abolished the therapeutic effect of indralin without affecting its radioprotective activity.

Correlation between antibodies to bisphenol A, its target enzyme protein disulfide isomerase and antibodies to neuron-specific antigens.

Evidence continues to increase linking autoimmunity and other complex diseases to the chemicals commonly found in our environment. Bisphenol A (BPA) is a synthetic monomer used widely in many forms, from food containers to toys, medical products and many others. The potential for BPA to participate as a triggering agent for autoimmune diseases is likely due to its known immunological influences. The goal of this research was to determine if immune reactivity to BPA has any correlation with neurological antibodies. BPA binds to a target enzyme called protein disulfide isomerase (PDI). Myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) are neuronal antigens that are target sites for neuroinflammation and neuroautoimmunity. We determined the co-occurrence of anti-MBP and anti-MOG antibodies with antibodies made against BPA bound to human serum albumin in 100 healthy human subjects. Correlation between BPA to PDI, BPA to MOG, BPA to MBP, PDI to MBP and PDI to MOG were all highly statistically significant (P < 0.0001). The outcome of our study suggests that immune reactivity to BPA-human serum albumin and PDI has a high degree of statistical significance with substantial correlation with both MBP and MOG antibody levels. This suggests that BPA may be a trigger for the production of antibodies against PDI, MBP and MOG. Immune reactivity to BPA bound to human tissue proteins may be a contributing factor to neurological autoimmune disorders. Further research is needed to determine the exact relationship of these antibodies with neuroautoimmunities. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.

Protective effect of Cordyceps militaris extract against bisphenol A induced reproductive damage.

This study aimed to investigate the protective effects of Cordyceps militaris (C. militaris) against reproductive damage induced by bisphenol A (BPA). Rats were administrated 200 mg/kg BPA for 4 weeks and treated with C. militaris (200, 400, and 800 mg/kg body weight/day). By the end of the fourth week, the level of oxidative damage, sperm parameters, hormone levels, and histopathological changes were examined. In the group that only received BPA, there was a significant decrease in body weight compared with the normal control (NC) group. C. militaris significantly alleviated the BPA-induced reproductive damage by increasing testicular superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and glutathione (GSH); as well as by reducing serum malondialdehyde (MDA). C. militaris not only obviously enhanced the levels of serum LH and T, but it also improved the sperm count and motility compared to the BPA-treated group. These results suggest that C. militaris could be used as a potential natural substance for preventing BPA induced reproductive damage. Abbreviations BPA: bisphenol A; SOD: superoxide dismutase; GSH: glutathione; GSH-PX: glutathione peroxidase; MDA: malondialdehyde; ROS: reactive oxygen species; T: testosterone; LH: luteinizing hormone; FSH: follicle-stimulating hormone; UPLC: ultra performance liquid chromatography; RIA: radioimmunoassay; q RT-PCR: quantitative real time PCR; NC: normal control group; BPA: 200 mg/kg BPA administered group; H: 800 mg/kg C. militaris extract administered group; LB, MB, and HB: 200 mg/kg BPA + 200 mg/kg, 400 mg/kg, and 800 mg/kg C. militaris administered group, respectively; VeB: 200 mg/kg BPA + 300 mg/kg Vitamin E administered group; Star: steroidogenic acute regulatory protein; 3ß-HSD: 3beta-hydroxyl-delta-5-steroid dehydrogenase; CYP11A1: cytochrome P 450 family 11 subfamily A member 1; CYP17A1: cytochrome P 450 family 17 subfamily A member 1.

Bisphenol A Increases the Migration and Invasion of Triple-Negative Breast Cancer Cells via Oestrogen-related Receptor Gamma.

Triple-negative breast cancer (TNBC) is characterized by great metastasis and invasion capability. Our study revealed that nanomolar bisphenol A (BPA), one of the most ubiquitous endocrine disruptors, can increase wound closure and invasion of both MDA-MB-231 and BT-549 cells. BPA treatment can increase protein and mRNA expression of matrix metalloproteinase-2 (MMP-2) and MMP-9, while had no effect on the expression of vimentin (Vim) and fibronectin (FN) in TNBC cells. The expression of G-protein-coupled receptor (GPER), which has been suggested to mediate rapid oestrogenic signals, was not varied in BPA-treated MDA-MB-231 and BT-549 cells. Its inhibitor G15 also had no effect on BPA-induced MMPs expression and cell invasion. Interestingly, BPA treatment can significantly increase the mRNA and protein expressions of oestrogen-related receptor γ (ERRγ), but not ERRα or ERRß, in both MDA-MB-231 and BT-549 cells. The knock-down of ERRγ can markedly attenuate BPA-induced expression of MMP-2 and MMP-9 in TNBC cells. BPA treatment can activate both ERK1/2 and Akt in TNBC cells. Both inhibitors of ERK1/2 (PD98059) and Akt (LY294002) can attenuate BPA-induced ERRγ expression and cell invasion of MDA-MB-231 cells. Collectively, our data revealed that BPA can increase the expression of MMPs and in vitro motility of TNBC cells via ERRγ. Both activation of ERK1/2 and Akt participated in this process. Our study suggests that more attention should be paid to the roles of xenoestrogens such as BPA in the development and progression of TNBC.

Melatonin controlled apoptosis and protected the testes and sperm quality against bisphenol A-induced oxidative toxicity.

Epidemiological reports have indicated a correlation between the increasing bisphenol A (BPA) levels in the environment and the incidence of male infertility. In this study, the protective effects of melatonin on BPA-induced oxidative stress and apoptosis were investigated in the rat testes and epididymal sperm. Melatonin (10 mg/kg body weight (bw)) was injected concurrently with BPA (50 mg/kg bw) for 3 and 6 weeks. The administration of BPA significantly increased oxidative stress in the testes and epididymal sperm. This was associated with a decrease in the serum testosterone level as well as sperm quality, chromatin condensation/de-condensation level, and the percentage of haploid germ cells in the semen. BPA administration caused a significant increase in apoptosis accompanied by a decrease in the expression of the antiapoptotic proteins Bcl-2 in the testes and epididymal sperm. The concurrent administration of melatonin decreased oxidative stress by modulating the levels of glutathione, superoxide dismutase, and catalase as well as the malondialdehyde and hydrogen peroxide concentrations in the testes and sperm. Melatonin sustained Bcl-2 expression and controlled apoptosis. Furthermore, melatonin maintained the testosterone levels, ameliorated histopathological changes, increased the percentages of seminal haploid germ cells, and protected sperm chromatin condensation process, indicating appropriate spermatogenesis with production of functional sperm. In conclusion, melatonin protected against BPA-induced apoptosis by controlling Bcl-2 expression and ameliorating oxidative stress in the testes and sperm. Thus, melatonin is a promising pharmacological agent for preventing the potential reproductive toxicity of BPA following occupational or environmental exposures.

Influence of α-tocopherol and α-lipoic acid on bisphenol-A-induced oxidative damage in liver and ovarian tissue of rats.

Bisphenol A (BPA) is a commonly used material in daily life, and it is argued to cause oxidative stress in liver and ovarian tissue. α-Lipoic acid (ALA) and α-tocopherol (ATF), two of the most effective antioxidants, may play a role in preventing the toxic effect. Therefore, the purpose of this study was to examine the beneficial effects of ALA, ATF, and that of ALA + ATF combination on oxidative damage induced by BPA. Female Wistar rats were divided into five groups (control, BPA, BPA + ALA, BPA + ATF, and BPA + ALA + ATF). BPA (25 mg/kg/day), ALA (100 mg/kg/day), and ATF (20 mg/kg/day) were administered for 30 days. The levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), liver malondialdehyde (L-MDA) and glutathione peroxidase (L-GPx), and ovarian malondialdehyde (Ov-MDA) and nitric oxide (Ov-NO) were significantly higher in the BPA-treated groups compared with the control group. The levels of AST and ALT decreased in the BPA + ALA, BPA + ATF, and BPA + ALA + ATF groups compared with the BPA group. Similarly, BPA + ALA or BPA + ATF led to decreases in L-MDA and Ov-MDA levels compared with the BPA group. However, the BPA + ALA + ATF group showed a significant decrease in L-MDA levels compared with the BPA + ALA group and the BPA + ATF group. The levels of L-GPx decreased in the BPA + ATF and the BPA + ALA + ATF groups compared with the BPA group. The administration of ATF and ALA + ATF significantly decreased the Ov-NO levels. This study demonstrates that BPA causes oxidative damage in liver and ovarian tissues. ALA, ATF, or their combination were found to be beneficial in preventing BPA-induced oxidative stress.

Genistein reduces the noxious effects of in utero bisphenol A exposure on the rat prostate gland at weaning and in adulthood.

Bisphenol A (BPA) is one hormonally active chemical with potential deleterious effects on reproductive organs, including breast and prostate. In contrast, genistein (GEN) is the major phytoestrogen of soy that presents potential protective effects against hormone-dependent cancers, including that of the prostate. Thus, pregnant Sprague-Dawley rats were treated with BPA at 25 or 250 µg/kg/day by gavage from gestational day (GD) 10-21 with or without dietary GEN at 250 mg/kg/chow (∼5.5 mg/kg/day). Then, male offspring from different litters were euthanized on post-natal day (PND) 21 and 180. At PND21, BPA 25 exposure induced early prostatic changes while dietary GEN attenuated some deleterious actions this xenoestrogen on epithelial cell proliferation levels, androgen receptor expression and prostatic architecture in male offspring. At PND180, a significant increase in incidence of prostatic multifocal inflammation/reactive hyperplasia and atypical hyperplasia were observed in male offspring from dams that received BPA 25. On the other hand, maternal GEN feeding attenuated some the adverse effects of BPA 25 on prostate disease at late-in-life. This way, the present findings point to preventive action of dietary GEN on deleterious effects of gestational BPA exposure in both early and late prostate development in offspring F1.

Candida albicans Inhibits Pseudomonas aeruginosa Virulence through Suppression of Pyochelin and Pyoverdine Biosynthesis.

Bacterial-fungal interactions have important physiologic and medical ramifications, but the mechanisms of these interactions are poorly understood. The gut is host to trillions of microorganisms, and bacterial-fungal interactions are likely to be important. Using a neutropenic mouse model of microbial gastrointestinal colonization and dissemination, we show that the fungus Candida albicans inhibits the virulence of the bacterium Pseudomonas aeruginosa by inhibiting P. aeruginosa pyochelin and pyoverdine gene expression, which plays a critical role in iron acquisition and virulence. Accordingly, deletion of both P. aeruginosa pyochelin and pyoverdine genes attenuates P. aeruginosa virulence. Heat-killed C. albicans has no effect on P. aeruginosa, whereas C. albicans secreted proteins directly suppress P. aeruginosa pyoverdine and pyochelin expression and inhibit P. aeruginosa virulence in mice. Interestingly, suppression or deletion of pyochelin and pyoverdine genes has no effect on P. aeruginosa's ability to colonize the GI tract but does decrease P. aeruginosa's cytotoxic effect on cultured colonocytes. Finally, oral iron supplementation restores P. aeruginosa virulence in P. aeruginosa and C. albicans colonized mice. Together, our findings provide insight into how a bacterial-fungal interaction can modulate bacterial virulence in the intestine. Previously described bacterial-fungal antagonistic interactions have focused on growth inhibition or colonization inhibition/modulation, yet here we describe a novel observation of fungal-inhibition of bacterial effectors critical for virulence but not important for colonization. These findings validate the use of a mammalian model system to explore the complexities of polymicrobial, polykingdom infections in order to identify new therapeutic targets for preventing microbial disease.

Activation of Autophagic Flux against Xenoestrogen Bisphenol-A-induced Hippocampal Neurodegeneration via AMP kinase (AMPK)/Mammalian Target of Rapamycin (mTOR) Pathways.

The human health hazards related to persisting use of bisphenol-A (BPA) are well documented. BPA-induced neurotoxicity occurs with the generation of oxidative stress, neurodegeneration, and cognitive dysfunctions. However, the cellular and molecular mechanism(s) of the effects of BPA on autophagy and association with oxidative stress and apoptosis are still elusive. We observed that BPA exposure during the early postnatal period enhanced the expression and the levels of autophagy genes/proteins. BPA treatment in the presence of bafilomycin A1 increased the levels of LC3-II and SQSTM1 and also potentiated GFP-LC3 puncta index in GFP-LC3-transfected hippocampal neural stem cell-derived neurons. BPA-induced generation of reactive oxygen species and apoptosis were mitigated by a pharmacological activator of autophagy (rapamycin). Pharmacological (wortmannin and bafilomycin A1) and genetic (beclin siRNA) inhibition of autophagy aggravated BPA neurotoxicity. Activation of autophagy against BPA resulted in intracellular energy sensor AMP kinase (AMPK) activation, increased phosphorylation of raptor and acetyl-CoA carboxylase, and decreased phosphorylation of ULK1 (Ser-757), and silencing of AMPK exacerbated BPA neurotoxicity. Conversely, BPA exposure down-regulated the mammalian target of rapamycin (mTOR) pathway by phosphorylation of raptor as a transient cell's compensatory mechanism to preserve cellular energy pool. Moreover, silencing of mTOR enhanced autophagy, which further alleviated BPA-induced reactive oxygen species generation and apoptosis. BPA-mediated neurotoxicity also resulted in mitochondrial loss, bioenergetic deficits, and increased PARKIN mitochondrial translocation, suggesting enhanced mitophagy. These results suggest implication of autophagy against BPA-mediated neurodegeneration through involvement of AMPK and mTOR pathways. Hence, autophagy, which arbitrates cell survival and demise during stress conditions, requires further assessment to be established as a biomarker of xenoestrogen exposure.

Benzophenone-1 and nonylphenol stimulated MCF-7 breast cancer growth by regulating cell cycle and metastasis-related genes via an estrogen receptor α-dependent pathway.

Endocrine-disrupting chemicals (EDC) are defined as environmental compounds that produce adverse health manifestations in mammals by disrupting the endocrine system. Benzophenone-1 (2,4-dihydroxybenzophenone, BP1) and nonylphenol (NP), which are discharged from numerous industrial products, are known EDC. The aim of this study was to examine the effects of BP1 and NP on proliferation and metastasis of MCF-7 human breast cancer cells expressing estrogen receptors (ER). Treatment with BP1 (10⁻5-10⁻7 M) and NP (10⁻6-10⁻7 M) promoted proliferation of MCF-7 cells similar to the positive control 17 -beta-estradiol (E2). When ICI 182,780, an ER antagonist, was co-incubated with E2, BP1, or NP, proliferation of MCF-7 cells returned to the level of a control. Addition of BP1 or NP markedly induced migration of MCF-7 cells similar to E2. To elucidate the underlying molecular mechanisms produced by these EDC, alterations in transcriptional and translational levels of proliferation and metastasis-related markers, including cyclin D1, p21, and cathepsin D, were determined. Data showed increase in expression of cyclin D1 and cathepsin D and decrease in p21 at both transcriptional and translational levels. However, BP1- or NP-induced alterations of these genes were blocked by ICI 182,780, suggesting that changes in expression of these genes may be regulated by an ERα-dependent pathway. In conclusion, BP1 and NP may accelerate growth of MCF-7 breast cancer cells by regulating cell cycle-related genes and promote cancer metastasis through amplification of cathepsin D.

Effects of dietary Corinthian currants (Vitis vinifera L., var. Apyrena) on atherosclerosis and plasma phenolic compounds during prolonged hypercholesterolemia in New Zealand White rabbits.

Corinthian currants are a rich source of phenolic compounds, which are known to exert beneficial effects on cardiovascular disease. The hypothesis tested is whether dietary supplementation with currants attenuates atherosclerosis and affects plasma phenolics during prolonged hypercholesterolemia in rabbits. Thirty New Zealand White rabbits were fed one of four diets (normal and supplemented with 10% currants, with 0.5% cholesterol, and with 0.5% cholesterol plus 10% currants) for eight weeks. Plasma lipids, glucose and hepatic enzymes were determined. Individual phenolic compounds were identified and quantified in plasma during the dietary intervention. At the end of the study, histological examinations of aorta and liver were performed. The high-cholesterol diet resulted in hypercholesterolemia and oxidative stress, increased aspartate aminotransferase (AST) activity and induced aortic and hepatic lesion formation. Corinthian currant supplementation attenuated atherosclerotic lesions, maintained AST within the normal range and reduced oxidative stress without affecting glucose concentrations. The p-OH-benzoic and p-OH-phenylacetic acids predominated at high concentrations in plasma and remained almost constant during the study in the group that received the normal rabbit chow and the groups given food with added cholesterol either alone or supplemented with currants. Currant supplementation to the normal diet resulted in the reduced absorption of phenolic compounds, as revealed by the measurement of their plasma metabolites, suggesting a regulatory mechanism at the gut level under normal conditions.