Role of Antioxidants in Alleviating Bisphenol A Toxicity

Cinnamic acid abrogates bisphenol A-induced hepatotoxicity via suppression of pro-inflammatory cytokine and modulation of gene expressions of antioxidant enzymes in rats

Bisphenol A (BPA) is regularly used to produce plastic products. Its hepatotoxicity has been unveiled. The effects of cinnamic acid on BPA exposure have not been comprehensively studied, and the key mechanism of action is yet to be unraveled. Rats were allocated into 5 groups. Group 1 (control) was given corn oil. Group 2 received BPA for 14 consecutive days. Group 3 received cinnamic acid at 50 mg/kg in co-administration with BPA while group 4 received cinnamic acid at 100 mg/kg, in co-administration with BPA. Cinnamic acid (CA) only (100 mg/kg) was given to group 5. BPA exposure significantly decreased catalase, glutathione-S-transferase, and superoxide dismutase activities and non-significantly diminished glutathione level. A reduction in the gene expression of catalase accompanied this. Our result showed significant gene elevation at the mRNA level of tumor necrosis factor-α and elevated malondialdehyde by BPA. The significantly elevated alanine transaminase and aspartate transaminase activities in addition to increased levels of total cholesterol, triglycerides, and very low-density lipoprotein with reduced high-density lipoprotein reflected the detrimental effect of BPA in the liver. Our results revealed that cinnamic acid could alleviate the increased pro-inflammatory cytokine level and oxidative stress by downregulating tumor necrosis factor-α gene. The histopathological evaluation confirmed the biochemical results. Hepatic alterations were ameliorated when cinnamic acid was co-administered with BPA. These findings suggest that downregulation of the TNF-α gene induced by cinnamic acid may participate in suppressing the BPA-induced oxidative stress. This offers a new idea to unmask the mechanism underlying cinnamic acid's interference with BPA-induced hepatic damage.

18β-glycyrrhetinic acid Mitigates bisphenol A-induced liver and renal damage: Inhibition of TNF-α/NF-κB/p38-MAPK, JAK1/STAT1 pathways, oxidative stress and apoptosis

Bisphenol A (BPA) has been commonly used in various consumer products, including water bottles, food containers, and canned food linings. However, there are concerns about its potential toxicity to human health, particularly its impact on the liver and kidneys. The objective of this research was to investigate the potential ameliorative effects of 18β-glycyrrhetinic acid (GA) against BPA-induced hepatotoxicity and nephrotoxicity in rats. The animals were supplemented with BPA (250 mg/kg b.w.) alone or with GA (50 and 100 mg/kg b.w.) for 14 days. GA treatment alleviated the BPA-induced hepato-renal tissue injuries through reducing the serum ALT, AST and ALP levels, and urea and creatinine levels. GA co-treatment also increased activities of SOD, CAT and GPx enzymes and levels of GSH, and suppressed MDA levels in BPA induced tissues. BPA also induced inflammation by increasing the levels of TNF-α, NF-κB, JAK1, STAT1, P38 MAPK and JNK in liver and kidney tissues and GA treatment ameliorated these effects. BPA triggered apoptosis by increasing caspase-3, Bax, and cytochrome c at protein levels and also by decreasing the antiapoptotic Bcl-2 level. However, treatment with GA (50 and 100 mg/kg) decreased apoptosis. Overall, our results have revealed the potential ameliorative mechanisms of GA, as a possible agent for BPA-induced hepatotoxicity and nephrotoxicity.

Protective effect of a novel furan hybrid chalcone against bisphenol A-induced craniofacial developmental toxicity in zebrafish embryos

Bisphenol A (BPA), a pervasive endocrine disruptor, is known to cause significant developmental toxicity, particularly affecting craniofacial structures through oxidative stress and apoptosis. A novel furan hybrid chalcone derivative, 3-(2-hydroxy-5-nitrophenyl)-1-(5-methylfuran-2-yl)prop-2-en-1-one (DK04), specifically with a hydroxyl group for its antioxidant properties and a nitro group for enhanced electron-withdrawing ability, was evaluated for its potential to mitigate these toxic effects. Zebrafish embryos were exposed to BPA and co-treated with various concentrations of DK04. Our results demonstrated that DK04 significantly reduced reactive oxygen species (ROS) generation and lipid peroxidation, increased antioxidant enzyme activities (SOD and CAT), and restored the balance between pro-apoptotic (p53) and anti-apoptotic (bcl2) genes. Furthermore, DK04 treatment improved bone mineralization and chondrogenesis by reversing BPA-induced disruptions in osteogenic markers (runx2, sox9a, bmp6, and mmp13a). The locomotion impairments observed in BPA-exposed embryos were also ameliorated by DK04, indicating its potential neuroprotective effects. These findings suggest that DK04 offers a multifaceted approach to counteract BPA toxicity, making it a promising candidate for therapeutic intervention. This research underscores the importance of developing prophylactic compounds to safeguard health against environmental toxicants like BPA. Future studies should focus on long-term safety and efficacy in mammalian models and explore synergistic effects with other protective agents to broaden the applications of DK04 and contribute to public health benefits.

The protection of bisphenol A-modulated miRNAs and targets by natural products

Bisphenol A (BPA) is a ubiquitous environmental pollutant with endocrine-disrupting functions. Identifying protective drugs and exploring the mechanisms against BPA are crucial in healthcare. Natural products exhibiting antioxidant properties are considered to be able to protect against BPA toxicity. Although BPA-modulated targets and miRNAs have been individually reported, their connections to natural products were rarely organized. With the help of a protein-protein interaction database (STRING), the relationship between individual BPA-modulated targets was interconnected to provide a systemic view. In this review, BPA-downregulated and -upregulated targets are classified, and their interactive network was innovatively analyzed using the bioinformatic database (STRING). BPA-modulated miRNAs were also retrieved and ingeniously connected to BPA-modulated targets. Moreover, a novel connection between BPA-countering natural products was integrated into BPA-modulated miRNAs and targets. All these targets-associated natural products and/or miRNAs were incorporated into the STRING network, providing systemic relationships. Overall, the BPA-modulated target-miRNA-protecting natural product axis was innovatively constructed, providing a straightforward direction for exploring the integrated BPA-countering effects and mechanisms of natural products.

Ficus lindsayana Leaf Extract Protects C2C12 Mouse Myoblasts Against the Suppressive Effects of Bisphenol-A on Myogenic Differentiation

Recently, toxicological and epidemiological research has provided strong support for the unfavorable effects of bisphenol-A (BPA, 2,2'-bis(4-hydroxyphenyl) propane) on myogenesis and its underlying mechanisms. Researchers have therefore been looking for new strategies to prevent or mitigate these injurious effects of BPA on the human body. It has been found that plant extracts may act as potential therapeutic agents or functional foods, preventing human diseases caused by BPA. We previously reported that Ficus lindsayana (FL) extract exhibits anti-inflammation activity in macrophages via suppressing the expression of inflammation-related molecules and anti-insulin resistance in inflammation-treated adipocytes. In this study, we investigated whether Ficus lindsayana leaf extract (FLLE) protects C2C12 mouse myoblasts against the suppressive effects of BPA on myogenic differentiation. The viability of BPA-stimulated C2C12 myoblasts was significantly increased when co-treated with FLLE (200 µg/mL), suggesting that the extract may lessen the inhibitory effects of BPA on cell division. We also found that FLLE significantly increased neo-myotube formation by inducing the fusion of myoblasts into multinucleated myotubes when compared to the BPA-treated control cells, without impacting cell viability. In addition, the levels of myogenin and myocyte enhancer factor 2A (MEF2A), which are crucial markers and regulators of myogenesis, were markedly increased by the addition of FLLE (50 µg/mL) to the BPA-treated C2C12 cells. This finding suggests that FLLE effectively improved myogenic differentiation in BPA-exposed myoblasts. FLLE treatment (50 µg/mL) significantly raised total Akt protein levels in the BPA-treated C2C12 cells, enhancing protein phosphorylation. In addition, FLLE (50 µg/mL) obviously increased the phosphorylation levels of p70S6K and 4E-BP1, key downstream targets of the Akt/mTOR signaling cascade, by elevating total p70S6K and 4E-BP1 levels. These results suggest that FLLE diminishes the decline in myogenic differentiation induced by BPA via the regulation of the myocyte differentiation-related signaling pathway. The information obtained from this study demonstrates the health benefits of this plant, which warrants further investigation as an alternative medicine, functional ingredient, or food supplement that can prevent the negative health effects of BPA or other toxicants.

Plastic harmful ingredients reduce the level of neurofilament light chain protein

Population exposure to plastics is increasing, and plasticizers are frequently detected in humans as important ingredients of plastic products. However, patterns of exposure to harmful ingredients of plastics and their effects on neurofilament light chain (NFL), a marker of active brain pathology, are currently inconclusive. Herein, we employed a range of statistical methods to thoroughly investigate the impact of 24 plastic hazardous ingredients and their varying exposure patterns on NFL concentrations in the blood of the general population in 533 participants. Generalized linear model revealed a positive correlation between Mono-isononyl phthalate and Mono (2-Ethyl- 5-Hydroxyhexyl) Phthalate (MEHHP) with NFL. Furthermore, a significant dose-response relationship was observed between MEHHP and NFL, while Butyl paraben and Mono (Hydroxy-Isononyl) Ester exhibited a distinct "inverted U-shaped" nonlinear pattern with NFL. Additionally, Weighted Quantile Sum model allowed us to identify the mixed effects of all 24 plastic hazardous ingredients, with Mono(2-Ethyl-5-Oxohexyl) Phthalate, Mono-isobutyl phthalate, Mon butyl Phthalate, Propyl paraben and Triclosan occupying prominent positions. Finally, the latent profile analysis categorized exposures into high, medium, and low patterns, confirming that higher exposure to plastic hazardous ingredients posed a significant risk factor for elevated NFL levels in the blood. Exposure to plastic hazardous ingredients significantly increases the risk of NFL, the present contributes to early detection and intervention to reduce the incidence of neurodevelopmental disorder.

The impact of Bisphenol-A on human reproductive health

Bisphenol-A (BPA) is a recognized endocrine-disrupting chemical used to produce several consumer goods and products. There has been widespread exposure to BPA because of increased industrial production and use of BPA-containing products. As a result of these exposures, BPA is found in several human body fluids and can cause endocrine disruption by interfering with hormone signaling pathways and epigenetic modifications. Therefore, human reproductive health and development have been adversely affected by BPA. This review aimed to consolidate existing knowledge on the impact of BPA on human reproductive health, examining its effects on both males and females. To achieve this, we systematically searched four databases for studies that associated BPA with reproductive health (male and female), after which we retrieved the important information from the selected articles. There was an association of reproductive health diseases with high BPA exposure. In males, BPA was associated with increased sperm alterations, altered reproductive hormone levels, and testicular atrophy. In females, there was an association of BPA exposure with hormonal imbalances, reduced ovarian reserve, and increased likelihood of conditions such as fibroids, polycystic ovarian syndrome, endometriosis and infertility. BPA's pervasive presence and its harmful effects on reproductive health underscore the need for global regulation and public awareness. Although substantial evidence from animal and in vitro studies supports the detrimental effects of BPA, there is a need for more human-focused research, particularly in developing countries, to confirm these findings. This review advocates for increased regulatory measures to limit BPA exposure.

Bisphenol A-induced oxidative stress increases the production of ovarian cancer stem cells in mice

Bisphenol A (BPA) belongs to the endocrine disruptor chemicals (EDCs) causing various reproductive disorders in females. We analysed the toxic effects of BPA in the uterus and ovaries. The BPA was administered orally with the repeated low dose (LD, 1 mg/kg) and high dose (HD, 5 mg/kg) of body weight on alternate days for 4 months via oral gavage to Swiss mice. BPA administration decreases body weight, ovarian weight and size at LD, but increases ovarian weight and size at HD. The uterus weight, length, and diameter were increased in both the treated groups. The histopathological data show decreased ovarian follicle size, epithelial hyperplasia, and lymphocytic infiltration in the ovary. The BPA-treated uterus shows increased vascularization, atrophied endometrium and myometrium, and endometrial hyperplasia (EH) with aberrant glandular growth. The cancer stem cells (CSCs) in the ovaries were identified based on staining with anti-mouse CD44 and anti-mouse CD133 antibodies and analysed by flow cytometry. Three different populations of ovarian CSCs: CD44+CD133-, CD44+CD133+, and CD44-CD133+, can be recognised based on the intensity of these receptors. CD44+CD133- and CD44+CD133+ cell percentages were increased in BPA-treated groups. CD44-CD133+ were increased in LD but decreased in HD. The BPA administration also induces ROS production, which decreases the expression of antioxidant genes Superoxide dismutase 1 (SOD1), Superoxide dismutase 2 (SOD2), Catalase (CAT), Glutathione peroxidase 1 (GPX1), and Forkhead box O3 (FOXO3) in ovarian cells. In conclusion, BPA exposure induced an inflammatory response, increased CSC proportions, induced ROS, and decreased antioxidant responses in the ovaries.

Probiotics as Potential Tool to Mitigate Nucleotide Metabolism Alterations Induced by DiNP Dietary Exposure in Danio rerio

Diisononyl phthalate, classified as endocrine disruptor, has been investigate to trigger lipid biosynthesis in both mammalian and teleostean animal models. Despite this, little is known about the effects of DiNP exposure at tolerable daily intake level and the possible mechanisms of its toxicity. Probiotics, on the other hand, were demonstrated to have beneficial effects on the organism's metabolism and recently emerged as a possible tool to mitigate the EDC toxicity. In the present study, using a metabolomic approach, the potential hepatic sex-related toxicity of DiNP was investigated in adult zebrafish together with the mitigating action of the probiotic formulation SLAB51, which has already demonstrated its ability to ameliorate gastrointestinal pathologies in animals including humans. Zebrafish were exposed for 28 days to 50 µg/kg body weight (bw)/day of DiNP (DiNP) through their diet and treated with 109 CFU/g bw of SLAB51 (P) and the combination of DiNP and SLAB51 (DiNP + P), and the results were compared to those of an untreated control group (C). DiNP reduced AMP, IMP, and GMP in the purine metabolism, while such alterations were not observed in the DiNP + P group, for which the phenotype overlapped that of C fish. In addition, in male, DiNP reduced UMP and CMP levels in the pyrimidine metabolism, while the co-administration of probiotic shifted the DiNP + P metabolic phenotype toward that of P male and closed to C male, suggesting the beneficial effects of probiotics also in male fish. Overall, these results provide the first evidence of the disruptive actions of DiNP on hepatic nucleotide metabolism and mitigating action of the probiotic to reduce a DiNP-induced response in a sex-related manner.

Geraniol alleviates liver injury induced by bisphenol A via modulating NLRP3/caspase-1 pathway and gut microbiota in mice model

Bisphenol A has become a global public health problem. As an antioxidant, geraniol has potential preventive effects against toxicity. This study analyzes the preventive effect of geraniol against BPA induced liver injury in CD-1 mice. Geraniol administration significantly ameliorated BPA induced liver damage by the increase in superoxide dismutase/catalase enzymatic activities, and decrease in malonaldehyde level; prompted a significant reduction in the expression levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6), and pyroptosis biomarkers (NLRP3, ASC, and caspase-1); up-regulated the expression of claudin-1, ZO-1, and occludin markedly, which exhibited intestinal barrier function. Also, geraniol treatment optimized the composition and diversity of gut microbiota. It may be summarized that geraniol showed protective effects on liver injury induced by BPA and further revealed that the mechanism might be located on improving intestinal physical barrier function, down-regulating pyroptosis biomarkers, and normalizing intestinal microbiota, consequently reducing inflammatory response in the liver.

Critical review on unveiling the toxic and recalcitrant effects of microplastics in aquatic ecosystems and their degradation by microbes

Production of synthetic plastic obtained from fossil fuels are considered as a constantly growing problem and lack in the management of plastic waste has led to severe microplastic pollution in the aquatic ecosystem. Plastic particles less than 5mm are termed as microplastics (MPs), these are pervasive in water and soil, it can also withstand longer period of time with high durability. It can be broken down into smaller particles and can be adsorbed by various life-forms. Most marine organisms tend to consume plastic debris that can be accumulated easily into the vertebrates, invertebrates and planktonic entities. Often these plastic particles surpass the food chain, resulting in the damage of various organs and inhibiting the uptake of food due to the accumulation of microplastics. In this review, the physical and chemical properties of microplastics, as well as their effects on the environment and toxicity of their chemical constituents are discussed. In addition, the paper also sheds light on the potential of microorganisms such as bacteria, fungi, and algae which play a pivotal role in the process of microplastics degradation. The mechanism of microbial degradation, the factors that affect degradation, and the current advancements in genetic and metabolic engineering of microbes to promote degradation are also summarized. The paper also provides information on the bacterial, algal and fungal degradation mechanism including the possible enzymes involved in microplastic degradation. It also investigates the difficulties, limitations, and potential developments that may occur in the field of microbial microplastic degradation.

Potential hazards of bisphenol A on the male reproductive system: Induction of programmed cell death in testicular cells

A common industrial chemical known as bisphenol A (BPA) has been linked to endocrine disruption and can interfere with hormonal signaling pathways in humans and animals. This comprehensive review aims to explore the detrimental consequences of BPA on reproductive organ performance and apoptosis induction, shedding light on the emerging body of evidence from laboratory animal studies. Historically, most studies investigating the connection between BPA and reproductive tissue function have mainly leaned on laboratory animal models. These studies have provided crucial insights into the harmful effects of BPA on several facets of reproduction. This review consolidates an increasing literature that correlates exposure to BPA in the environment with a negative impact on human health. It also integrates findings from laboratory studies conducted on diverse species, collectively bolstering the mounting evidence that environmental BPA exposure can be detrimental to both humans and animals, particularly to reproductive health. Furthermore, this article explores the fundamental processes by which BPA triggers cell death and apoptosis in testicular cells. By elucidating these mechanisms, this review aids a deeper understanding of the complex interactions between BPA and reproductive tissues.

Effects of bisphenol A on reproduction, oxidative stress, and lipid regulation in the marine rotifer Brachionus plicatilis

This study reports the effects of bisphenol A (BPA) on the rotifer Brachionus plicatilis, focusing on growth performance, reproductive output, oxidative stress responses, and lipid metabolism genes. High BPA levels disrupted peak daily offspring production and led to oxidative stress and increased superoxide dismutase and catalase activity. The research identified distinctive monoacylglycerol O-acyltransferase (MGAT) and diacylglycerol O-acyltransferase (DGAT) genes in B. plicatilis, B. rotundiformis, and B. koreanus, enhancing understanding of lipid metabolism in these species. BPA exposure significantly altered MGAT and DGAT expression, and feeding status affected these regulatory patterns. When food was unavailable, BPA reduced DGAT2 and MGAT2a expression. However, under feeding conditions, DGAT2 and MGAT1 levels increased, indicating that nutritional status and BPA exposure interact to affect gene expression.

The Protective Effect of Gallic Acid Against Bisphenol A-Induced Ovarian Toxicity and Endocrine Disruption in Female Rats

Purpose: This study aimed to investigate the protective effects of gallic acid (GA) against ovarian damage induced by bisphenol A (BPA) exposure in female rats. We evaluated whether GA can mitigate the adverse effects of BPA on ovarian structure, inflammatory markers, oxidative stress, apoptosis, and reproductive hormone levels. Methods: Thirty-two female rats were categorized into four groups: control, GA, BPA, and GA+BPA. Histopathological evaluations of ovarian tissue were performed using hematoxylin-eosin staining. The immunohistochemical analysis was conducted for inflammatory, oxidative DNA damage, and apoptotic markers (Tumor necrosis factor alpha [TNFα], cyclooxygenase-2 [COX2], interleukin-1 beta [IL-1β], 8-hydroxydeoxyguanosine [8-OHdG], and caspase 3). Oxidative stress was assessed by measuring malondialdehyde and superoxide dismutase levels. Furthermore, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen, and progesterone levels were quantified using enzyme-linked immunosorbent assay. Results: Histopathological outcomes revealed that BPA significantly induced follicular degeneration, which was effectively mitigated by GA treatment (P < 0.05). Immunohistochemical analysis highlighted the exacerbation of inflammatory responses and oxidative DNA damage and apoptosis (TNFα, COX-2, IL-1β, 8-OHdG, and caspase 3) in BPA-exposed tissues, which were reduced in the presence of GA (P < 0.05). The assessment of oxidative stress demonstrated that GA could significantly decrease lipid peroxidation and partially restore antioxidant defense mechanisms disrupted by BPA (P < 0.05). Hormonal profiling indicated that BPA exposure altered the levels of FSH, LH, estrogen, and progesterone, with GA treatment showing a capacity to modulate these changes, especially in progesterone levels (P < 0.05). Conclusions: The findings suggest that GA exhibits protective properties against BPA-induced ovarian damage through its antioxidative and anti-inflammatory activities, alongside its ability to modulate hormonal imbalances. This research underscores the therapeutic potential of GA in safeguarding reproductive health against environmental toxicants.

Bisphenol A-What Do We Know? A Global or Local Approach at the Public Health Risk Level

BPA has demonstrated enormous multisystem and multi-organ toxicity shown mainly in animal models. Meanwhile, the effects of its exposure in humans still require years of observation, research, and answers to many questions. Even minimal and short-term exposure contributes to disorders or various types of dysfunction. It is released directly or indirectly into the environment at every stage of the product life cycle, demonstrating its ease of penetration into the body. The ubiquity and general prevalence of BPA influenced the main objective of the study, which was to assess the toxicity and health effects of BPA and its derivatives based on the available literature. In addition, the guidelines of various international institutions or regions of the world in terms of its reduction in individual products were checked. Bisphenol A is the most widely known chemical and perhaps even the most studied by virtually all international or national organizations, but nonetheless, it is still controversial. In general, the level of BPA biomonitoring is still too high and poses a potential threat to public health. It is beginning to be widely argued that future toxicity studies should focus on molecular biology and the assessment of human exposure to BPA, as well as its substitutes. The effects of its exposure still require years of observation, extensive research, and answers to many questions. It is necessary to continue to deepen the knowledge and interest of many organizations, companies, and consumers around the world in order to make rational purchases as well as future choices, not only consumer ones.

Bisphenol A and its structural analogues exhibit differential potential to induce mitochondrial dysfunction and apoptosis in human granulosa cells

Bisphenol A (BPA) is an endocrine disruptor strongly associated with ovarian dysfunction. BPA is being substituted by structurally similar chemicals, such as bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF). However, the toxicity of these analogues in female reproduction remains largely unknown. This study evaluated the effects of BPA and its analogues BPS, BPF, and BPAF on the mitochondrial mass and function, oxidative stress, and their potential to induce apoptosis of human granulosa cells (KGN cells). BPA and its analogues, especially BPA and BPAF, significantly decreased mitochondrial activity and cell viability. The potential of bisphenols to reduce mitochondrial mass and function differed in the following order: BPAF > BPA > BPF > BPS. Flow cytometry revealed that exposure to bisphenols significantly increased mitochondrial ROS levels and increased mitochondrial Ca2+ levels. Thus, bisphenols exposure causes mitochondrial stress in KGN cells. At the same time, bisphenols exposure significantly induced apoptosis. These results thus emphasize the toxicity of these bisphenols to cells. Our study suggests the action mechanism of BPA and its analogues in damage caused to ovarian granulosa cells. Additionally, these novel analogues may be regrettable substitutes, and the biological effects and potential risks of BPA alternatives must be evaluated.

Exploring novel insights into the molecular mechanisms underlying Bisphenol A-induced toxicity: A persistent threat to human health

Bisphenol A (BPA) is a ubiquitous industrial chemical used in the production of polycarbonate plastics and epoxy resins, found in numerous consumer products. Despite its widespread use, its potential adverse health effects have raised significant concerns. This review explores the molecular mechanisms and evidence-based literature underlying BPA-induced toxicities and its implications for human health. BPA is an endocrine-disrupting chemical (EDC) which exhibits carcinogenic properties by influencing various receptors, such as ER, AhR, PPARs, LXRs, and RARs. It induces oxidative stress and contributes to cellular dysfunction, inflammation, and DNA damage, ultimately leading to various toxicities including but not limited to reproductive, cardiotoxicity, neurotoxicity, and endocrine toxicity. Moreover, BPA can modify DNA methylation patterns, histone modifications, and non-coding RNA expression, leading to epigenetic changes and contribute to carcinogenesis. Overall, understanding molecular mechanisms of BPA-induced toxicity is crucial for developing effective strategies and policies to mitigate its adverse effects on human health.

Application of the Key Characteristics of Carcinogens to Bisphenol A

The ten key characteristics (KCs) of carcinogens are based on characteristics of known human carcinogens and encompass many types of endpoints. We propose that an objective review of the large amount of cancer mechanistic evidence for the chemical bisphenol A (BPA) can be achieved through use of these KCs. A search on metabolic and mechanistic data relevant to the carcinogenicity of BPA was conducted and web-based software tools were used to screen and organize the results. We applied the KCs to systematically identify, organize, and summarize mechanistic information for BPA, and to bring relevant carcinogenic mechanisms into focus. For some KCs with very large data sets, we utilized reviews focused on specific endpoints. Over 3000 studies for BPA from various data streams (exposed humans, animals, in vitro and cell-free systems) were identified. Mechanistic data relevant to each of the ten KCs were identified, with receptor-mediated effects, epigenetic alterations, oxidative stress, and cell proliferation being especially data rich. Reactive and bioactive metabolites are also associated with a number of KCs. This review demonstrates how the KCs can be applied to evaluate mechanistic data, especially for data-rich chemicals. While individual entities may have different approaches for the incorporation of mechanistic data in cancer hazard identification, the KCs provide a practical framework for conducting an objective examination of the available mechanistic data without a priori assumptions on mode of action. This analysis of the mechanistic data available for BPA suggests multiple and inter-connected mechanisms through which this chemical can act.

Associations of Bisphenols Exposure and Hyperuricemia Based on Human Investigation and Animal Experiments

Hyperuricemia is characterized by elevated blood uric acid (UA) levels, which can lead to certain diseases. Epidemiological studies have explored the association between environmental contaminant exposure and hyperuricemia. However, few studies have investigated the role of chemical exposure in the development of hyperuricemia. Here, we sought to investigate the effects of bisphenol exposure on the occurrence of hyperuricemia. Fifteen bisphenol chemicals (BPs) were detected in human serum and urine samples collected from an area with a high incidence of hyperuricemia in China. Serum UA levels positively correlated with urinary bisphenol S (BPS), urinary bisphenol P (BPP), and serum bisphenol F (BPF). The effects of these three chemicals on UA levels in mice were explored at various exposure concentrations. An increase in serum UA levels was observed in BPS- and BPP-exposed mice. The results showed that BPS exposure increased serum UA levels by damaging the structure of the kidneys, whereas BPP exposure increased serum UA levels by disturbing purine metabolism in the liver. Moreover, BPF did not induce an increase in serum UA levels owing to the inhibition of guanine conversion to UA. In summary, we provide evidence of the mechanisms whereby exposure to three BPs disturbs UA homeostasis. These findings provide new insights into the risks of exposure to bisphenol chemicals.

18β-Glycyrrhetinic acid exerts cardioprotective effects against BPA-induced cardiotoxicity through antiapoptotic and antioxidant mechanisms

Bisphenol A (BPA) is a synthetic environmental pollutant widely used in industry, as well as is an endocrine disrupting chemicals and has a toxic effects on heart tissue. The aim of this study is to reveal the cardioprotective effects of 18β-glycyrretinic acid (GA) against BPA-induced cardiotoxicity in rats. In this study, 40 male rats were used and five different groups (each group includes eight rats) were formed. The rats were applied BPA (250 mg/kg b.w.) alone or with GA (50 and 100 mg/kg b.w.) for 14 days. Rats were killed on Day 15 and heart tissues were taken for analysis. GA treatment decreased serum lactate dehydrogenase and creatine kinase MB levels, reducing BPA-induced heart damage. GA treatment showed ameliorative effects against lipid peroxidation and oxidative stress caused by BPA by increasing the antioxidant enzyme activities (glutathione peroxidase, superoxide dismutase, and catalase) and GSH level of the heart tissue and decreasing the MDA level. In addition, GA showed antiapoptotic effect by increasing Bcl-2, procaspase-3, and -9 protein expression levels and decreasing Bax, cytochrome c, and P53 protein levels in heart tissue. As a result, it was found that GA has cardioprotective effects on heart tissue by exhibiting antioxidant and antiapoptotic effects against heart damage caused by BPA, an environmental pollutant. Thus, it was supported that GA could be a potential cardioprotective agent.

Assembled Bisphenol A with cyclic oligosaccharide as the controlled release complex to reduce risky effects

Herein, in order to improve the bioavailability of a non-biodegradable pollutant, inclusion complexation procedures had been used to develop better formulations of this pollutant, Bisphenol A (BPA). In our research, an inclusion complex (IC) of β-cyclodextrin (β-CD) with BPA was formed to investigate the effect of β-CD on the water solubility, anti-oxidant, anti-bacterial activity, toxicity, and thermal stability of BPA. UV-Vis and other spectrometric methods such as NMR, FTIR, and XRD indicated the molecular mechanism of interactions between β-CD and BPA, which was further hypothesized using molecular modeling to confirm preliminary results. Studies of TGA and DSC demonstrated that encapsulation boosted the thermal stability of BPA. This research also makes predictions about BPA's release behavior when CT-DNA is present. In vitro testing of the IC's antibacterial activities showed that it outperformed pure BPA. The in silico study was found to have a considerable decrease in toxicity level for IC compared to pure BPA. Therefore, β-CD-encapsulated BPA can lessen toxicity by raising antioxidant levels. Additionally, as its antibacterial activity increases, it may be employed therapeutically. Thus, this discovery of creating BPA formulations with controlled release and/or protective properties allows for a more logical application of BPA by reducing its hazardous effects through boosting its efficacy.

Naringenin ameliorates cytotoxic effects of bisphenol A on mouse Sertoli cells by suppressing oxidative stress and modulating mitophagy: An experimental study

Background

Bisphenol A (BPA), an endocrine-disrupting agent, is widely used as polycarbonate plastics for producing food containers. BPA exposure at environmentally relevant concentrations can cause reproductive disorders.

Objective

The effect of Naringenin (NG) on BPA-induced Sertoli cell toxicity and its mechanism was examined in the present study.

Materials and Methods

In this experimental-laboratory study, the mouse TM4 cells were treated to BPA (0.8 μM) or NG for 24 hr at concentrations of 10, 20, and 50 μg/ml. Cell viability, reactive oxygen species (ROS) production, malondialdehyde (MDA) content, antioxidant level, and mitochondrial membrane potential (MMP) were examined. The expression of mitophagy-related genes, including Parkin and PTEN-induced putative kinase 1 (Pink1), was also evaluated.

Results

BPA significantly lowered the viability of the Sertoli cells (p= 0.004). Pink1 and Parkin levels of the BPA group were significantly increased (p < 0.001), while the MMP was considerably decreased (p < 0.001). BPA raised MDA and ROS levels (p < 0.001) and reduced antioxidant biomarkers (p= 0.003). NG at the 20 and 50 μg/ml concentrations could significantly improve the viability and MMP of TM4 cells (p= 0.034). NG depending on concentration, could decrease Pink1 and Parkin at mRNA and protein levels compared to the BPA group (p = 0.024). NG enhanced antioxidant factors, while ROS and MDA levels were decreased in the BPA-exposed cells.

Conclusion

The beneficial impacts of NG on BPA-exposed Sertoli cells are related to the suppression of mitophagy and the reduction of oxidative stress.

Adverse (geno)toxic effects of bisphenol A and its analogues in hepatic 3D cell model

Bisphenol A (BPA) is one of the most widely used and versatile chemical compounds in polymer additives and epoxy resins for manufacturing a range of products for human applications. It is known as endocrine disruptor, however, there is growing evidence that it is genotoxic. Because of its adverse effects, the European Union has restricted its use to protect human health and the environment. As a result, the industry has begun developing BPA analogues, but there are not yet sufficient toxicity data to claim that they are safe. We investigated the adverse toxic effects of BPA and its analogues (BPS, BPAP, BPAF, BPFL, and BPC) with emphasis on their cytotoxic and genotoxic activities after short (24-h) and prolonged (96-h) exposure in in vitro hepatic three-dimensional cell model developed from HepG2 cells. The results showed that BPFL and BPC (formed by an additional ring system) were the most cytotoxic analogues that affected cell viability, spheroid surface area and morphology, cell proliferation, and apoptotic cell death. BPA, BPAP, and BPAF induced DNA double-strand break formation (γH2AX assay), whereas BPAF and BPC increased the percentage of p-H3-positive cells, indicating their aneugenic activity. All BPs induced DNA single-strand break formation (comet assay), with BPAP (≥0.1 μM) being the most effective and BPA and BPC the least effective (≥1 μM) under conditions applied. The results indicate that not all of the analogues studied are safer alternatives to BPA and thus more in-depth research is urgently needed to adequately evaluate the risks of BPA analogues and assess their safety for humans.

Neurotoxicity of Bisphenol A and the Impact of Melatonin Administration on Oxidative Stress, ERK/NF-kB Signaling Pathway, and Behavior in Rats

Bisphenol A (BPA) exposure can be associated with neurodevelopmental disorders due to impairment of cell proliferation and synaptic development. Our study evaluated the effects of melatonin (MEL) on ambulatory activity, lipid peroxidation, cytokines, ERK/NF-kB signaling pathway in the hippocampus and frontal lobe, and histopathological changes in the hippocampus of the BPA-treated rats. The animals were divided into 4 groups: control, BPA, BPA + MEL I, and BPA + MEL II. MEL I (20 mg/kg b.w.) and MEL II (40 mg/kg b.w.) were orally administered for 28 days. On the 29th day, BPA (1 mg/kg b.w.) was intraperitoneally administered, and, after 24 h, an open field test (OFT) and an elevated plus maze (EPM) were conducted. The results showed that the MEL II group made significantly more entries in the open arms of EPM, traveled significantly greater distance, and spent more time in the central part of OFT. Malondialdehyde levels were diminished by MEL II in the hippocampus and by MEL I in the frontal lobe. In the hippocampus, the MAPK level was significantly lowered by both doses of MEL (p < 0.05) while in the frontal lobe, only MEL II reduced the MAPK activation. MEL I and II significantly decreased the γH2AX and upregulated the NFkB and pNFkB expressions in the hippocampus while MEL II downregulated the MCP1 expression. Both doses of MEL attenuated the BPA-evoked histopathological alterations in the hippocampus. These data indicate that MEL can mediate the neuroprotection against BPA-induced neurotoxicity and improves behavioral changes suggesting a real potential as a protective agent in brain toxicity.

Transplantation of adipose-derived mesenchymal stem cells ameliorates acute hepatic injury caused by nonsteroidal anti-inflammatory drug diclofenac sodium in female rats

BACKGROUND

Although the beneficial role of adipose-derived mesenchymal stem cells (AD-MSCs) in acute liver injury has been addressed by numerous studies employing different liver injury inducers, the role of rat AD-MSCs (rAD-MSCs) in diclofenac sodium (DIC) - induced acute liver injury has not yet been clarified.

OBJECTIVE

This study aimed to investigate whether rat adipose- rAD-MSCs injected intraperitoneal could restore the DIC-induced hepatoxicity.

METHODS

Hepatotoxicity was induced by DIC in a dose-based manner, after which intraperitoneal injection of rAD-MSCs was performed.

RESULTS

Here, the transplanted cells migrated to the injured liver, and this was evidenced by detecting the specific SRY in the liver samples. After administering DIC, a significant decrease in body weight, survival rate, serum proteins, antioxidants, anti-apoptotic gene expression, and certain growth factors, whereas hepatic-specific markers, pro-inflammatory mediators, and oxidative, pro-apoptotic, and ER-stress markers were elevated. These adverse effects were significantly recovered after engraftment with rAD-MSCs. This was evidenced by enhanced survival and body weight, improved globulin and albumin values, increased expression of SOD, GPx, BCL-2, VEGF, and FGF-basic expression, and decreased serum ALT, AST, ALP, and total bilirubin. rAD-MSCs also reduced liver cell damage by suppressing the expression of MDA, IL-1B, IL-6, BAX, JNK, GRP78/BiP, CHOP, XBP-1, and cleaved caspase 3/7. Degenerative hepatic changes and multifocal areas of fatty change within liver cells were observed in DIC-received groups. These changes were improved with the transplantation of rAD-MSCs.

CONCLUSIONS

We could conclude that targeted AD-MSCs could be applied to reduce hepatic toxicity caused by NSAIDs (DIC).

Degradation of bisphenol A: a contaminant of emerging concern, using catalytic ozonation by activated carbon impregnated nanocomposite-bimetallic catalyst

Rampant water pollution events and rising water demand caused by exponential population growth and depleting freshwater resources speak of an impending water crisis. The inability of conventional wastewater treatment systems to remove contaminants of emerging concern (CECs) such as bisphenol A (BPA) beckons for new and efficient technologies to remove them from wastewater and water sources. Advanced oxidation processes such as ozonation are primarily known for their capability to oxidize and degrade organic entities in water, but optimum mineralization levels were hard to achieve. In this study, we synthesized an activated carbon impregnated nanocomposite-bimetallic catalyst (AC/CeO₂/ZnO) and used it along with ozonation to remove BPA from water. The catalyst was characterized using BET, XRD, FESEM, Raman spectra, and DLS studies. Catalytic ozonation achieved TOC removal 25% higher than non-catalytic ozonation process. The degradation pathway of BPA was proposed using LC-MS/LC-Q-TOF studies that found six main aromatic degradation byproducts. Catalytic ozonation and non-catalytic ozonation followed similar degradation pathways. The formation of persistent aliphatic acidic byproducts in the treated sample made total organic carbon (TOC) removal above 61% difficult.

Melatonin improves bisphenol A-induced cell apoptosis, oxidative stress and autophagy impairment via inhibition of the p38 MAPK signaling pathway in FLK-BLV cells

The aim of this study was to assess the protective effect and potential mechanism of melatonin against bisphenol A (BPA)-induced apoptosis and oxidative damage in FLK-BLV cells. The results showed that BPA reduced cell viability in a dose- and time-dependent manner, caused cell shrinkage and induced oxidative stress and apoptosis in FLK-BLV cells, which were effectively reversed by melatonin. In addition, BPA caused autophagy flux impairment, which was confirmed by the increased of LC3-II and p62 levels, whereas melatonin treatment effectively reduced p62 levels under BPA treatment, and reversed apoptosis-related protein expression patterns caused by BPA. However, inhibition of autophagy by CQ partially abolished the protective effect of melatonin on apoptosis, suggesting that melatonin against BPA-induced oxidative injury and apoptosis by activating autophagy pathway. Moreover, we found that melatonin inhibited BPA-induced the activation of p38 MAPK, which was comparable to SB203580 pretreatment, and companied by the activation of autophagy and decreases of apoptosis when compared to BPA alone, indicating that melatonin protected against BPA-induced apoptosis partially through the p38 MAPK-autophagy pathway. In conclusion, these results suggest that melatonin may prevent BPA-induced FLK-BLV cell damage by inhibiting p38/MAPK signaling pathway and activating autophagy, and it could be a potential therapeutic compound in preventing BPA-induced cell damage.

Does ( -)-epigallocatechin-3-gallate protect the neurotoxicity induced by bisphenol A in vivo?

Bisphenol A (BPA) is one of the chemicals that is firmly accompanied by hippocampal neuronal injury. As oxidative stress appears to be a major contributor to neurotoxicity induced by BPA, antioxidants with remarkable neuroprotective effects can play a valuable protective role. Around the world, ( -)-epigallocatechin-3-gallate (EGCG) was one of the most popular antioxidants that could exert a beneficial neuroprotective role. Here, we examined the potential efficiency of EGCG against neurotoxicity induced by BPA in the hippocampal CA3 region of the rat model. This study revealed that EGCG was unable to abrogate the significant decrease in circulating adiponectin level and hippocampal superoxide dismutase activity as well as an increase in hippocampal levels of nitric oxide and malondialdehyde. Notably, EGCG failed to antagonize the oxidative inhibitory effect of BPA on hippocampal neurotransmission and its associated cognitive deficits. In addition, the histopathological examination with immunohistochemical detection of caspase-3 and NF-kB/p65 emphasized that EGCG failed to protect hippocampal CA3 neurons from apoptotic and necrotic effects induced by BPA. Our study revealed that EGCG showed no protective role against the neurotoxic effect caused by BPA, which may be attributed to its failure to counteract the BPA-induced oxidative stress in vivo. The controversial effect is probably related to EGCG's ability to impede BPA glucuronidation and thus, its detoxification. That inference requires further additional experimental and clinical studies.

Obesity II: Establishing causal links between chemical exposures and obesity

Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.

BPA and its analogs increase oxidative stress levels in in vitro cultured granulosa cells by altering anti-oxidant enzymes expression

Bisphenol A is a widespread endocrine disruptor with numerous effects on reproductive functions. Limitations on BPA in manufacturing has prompted the use of analogs, such as BPS and BPF, with limited research on their safety. The objective of this study was to evaluate the effects of BPA and its analogs on oxidative stress levels within bovine granulosa cells and to measure the expression of key antioxidant genes. Results indicate that BPA and BPF reduce cell viability and induce mitochondrial dysfunction and all three bisphenols increased production of reactive oxygen species as early as 12hrs post exposure. BPA increased the levels of antioxidants at 12hrs at the mRNA and protein levels, while these results were not significant at 48hrs. These results together suggest that BPA and its analogs can induce oxidative stress within bovine granulosa cells, although not necessarily through common mechanisms. Therefore, the use of BPA analogs may have to be re-considered.

Can Antioxidants Reduce the Toxicity of Bisphenol?

BPA is still the subject of extensive research due to its widespread use, despite its significant toxicity resulting not only from its negative impact on the endocrine system but also from disrupting the organism’s oxidative homeostasis. At the molecular level, bisphenol A (BPA) causes an increased production of ROS and hence a change in the redox balance, mitochondrial dysfunction, and modulation of cell signaling pathways. Importantly, these changes accumulate in animals and humans, and BPA toxicity may be aggravated by poor diet, metabolic disorders, and coexisting diseases. Accordingly, approaches using antioxidants to counteract the negative effects of BPA are being considered. The preliminary results that are described in this paper are promising, however, it should be emphasized that further studies are required to determine the optimal dosage and treatment regimen to counteract BPA toxicity. It also seems necessary to have a more holistic approach showing, on the one hand, the influence of BPA on the overall human metabolism and, on the other hand, the influence of antioxidants in doses that are acceptable with the diet on BPA toxicity. This is due in part to the fact that in many cases, the positive effect of antioxidants in in vitro studies is not confirmed by clinical studies. For this reason, further research into the molecular mechanisms of BPA activity is also recommended.

Neurotoxicity and neuroinflammatory effects of bisphenol A in male rats: the neuroprotective role of grape seed proanthocyanidins

Exposure to bisphenol A (BPA) contributes to neurological disorders, but the underlying mechanisms are still not completely understood. We studied the neurotoxic effect of BPA and how it promotes inflammation and alteration in the neurotransmission synthesis, release, and transmission. This study was also designed to investigate the neuroprotective effect of grape seed proanthocyanidins (GSPE) against BPA-induced neurotoxicity in rats. Rats were equally divided into 4 groups with 7 rats in each: control group, BPA group, GSPE + BPA group, and GSPE group. Rats were orally treated with their respective doses (50 mg BPA/kg BW and/or 200 mg GSPE/kg BW) daily for 70 days. BPA elicits significant elevation in malondialdehyde (MDA) and nitric oxide (NO) associated with a significant reduction in glutathione (GSH), total thiols, glutathione peroxidase (GPx), superoxide dismutase (SOD), and glutathione-S-transferase (GST). BPA exposure results in increased dopamine and serotonin levels, elevation in acetylcholinesterase (AChE) activity, and reduction in Na/K-ATPase and total ATPase activities in the brain. Also, BPA induces upregulation in the gene expression of the inflammatory markers, tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2), and in the tumor suppressor and pro-oxidant p53 protein. The pretreatment with GSPE attenuates or ameliorate all the oxidative and neurotoxic parameters induced by BPA. Our results suggest that GSPE has a promising role in modulating BPA-induced neuroinflammation and neurotoxicity and its antioxidant and free radical scavenging activities may in part be responsible for such effects.

Role of Functional Monomers upon the Properties of Bisphenol A Molecularly Imprinted Silica Films

In this study, two types of bisphenol A molecularly imprinted films (BPA-MIP) were successfully prepared via sol-gel derived methods using two different organosilane functional monomers N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (DAMO-T) or (3-mercaptopropyl)trimethoxysilane (MPTES). The physical-chemical characterization of films, in terms of morphology, structure, thermal analysis, and optical features, suggested that thinner films with a homogenous porous structure were more likely to retain BPA molecules. The MIP films revealed the rapid and quantitative adsorption of BPA, registering the most specific binding in the first five minutes of contact with the BPA-MIP film. Silica films were effectively regenerated for further usage for at least five times, demonstrating their high stability and reusability. Even if the performance of films for BPA uptake dropped dramatically after the third adsorption/reconditioning cycle, this synthesis method for BPA-MIP films has proven to be a reliable and cheap way to prepare sensitive films with potential application for re-usable optical sensors.

Fighting Bisphenol A-Induced Male Infertility: The Power of Antioxidants

Bisphenol A (BPA), a well-known endocrine disruptor present in epoxy resins and polycarbonate plastics, negatively disturbs the male reproductive system affecting male fertility. In vivo studies showed that BPA exposure has deleterious effects on spermatogenesis by disturbing the hypothalamic–pituitary–gonadal axis and inducing oxidative stress in testis. This compound seems to disrupt hormone signalling even at low concentrations, modifying the levels of inhibin B, oestradiol, and testosterone. The adverse effects on seminal parameters are mainly supported by studies based on urinary BPA concentration, showing a negative association between BPA levels and sperm concentration, motility, and sperm DNA damage. Recent studies explored potential approaches to treat or prevent BPA-induced testicular toxicity and male infertility. Since the effect of BPA on testicular cells and spermatozoa is associated with an increased production of reactive oxygen species, most of the pharmacological approaches are based on the use of natural or synthetic antioxidants. In this review, we briefly describe the effects of BPA on male reproductive health and discuss the use of antioxidants to prevent or revert the BPA-induced toxicity and infertility in men.