Environmental toxins and the impact of other endocrine disrupting chemicals in women's reproductive health

The Effect of Various Environmental Pollutants on the Reproductive Health in Children: A Brief Review of the Literature

PURPOSE OF REVIEW

Environmental pollutants in air, water, soil, and food are a significant concern due to their potential adverse effects on fetuses, newborns, babies, and children. These chemicals, which pass to fetuses and babies through trans-placental transfer, breast milk, infant formula, dermal transfer, and non-nutritive ingestion, can cause health problems during childhood. This review aims to discuss how exposure to various environmental pollutants in early life stages can disrupt reproductive health in children.

RECENT FINDINGS

Environmental pollutants can affect Leydig cell proliferation and differentiation, decreasing testosterone production throughout life. This may result in cryptorchidism, hypospadias, impaired semen parameters, and reduced fertility. Although many studies on female reproductive health cannot be interpreted to support causal relationships, exposure to pollutants during critical windows may subsequently induce female reproductive diseases, including early or delayed puberty, polycystic ovary syndrome, endometriosis, and cancers. There is growing evidence that fetal and early-life exposure to environmental pollutants could affect reproductive health in childhood. Although diet is thought to be the primary route by which humans are exposed to various pollutants, there are no adopted nutritional interventions to reduce the harmful effects of pollutants on children's health. Therefore, understanding the impact of environmental contaminants on various health outcomes may inform the design of future human nutritional studies.

p,p'-DDT induces apoptosis in human endometrial stromal cells via the PI3K/AKT pathway and oxidative stress

OBJECTIVE

Bis-[4-chlorophenyl]-1,1,1-trichloroethane (DDT), one of the most widely used synthetic pesticides, is an endocrine-disrupting chemical with the potential to interfere with the human reproductive system. The effects of DDT and one of its metabolites, p,p'-DDT, on human endometrial stromal cells (ESCs) and health outcomes remain unknown. In this study, we investigated whether p,p'-DDT induces an imbalance in cell proliferation and apoptosis in human ESCs via oxidative stress.

METHODS

We assessed apoptosis in ESCs by quantifying the expression of markers associated with both intrinsic and extrinsic pathways. Additionally, we measured levels of reactive oxygen species (ROS), antioxidant enzyme activity, and estrogen receptors (ERs). We also examined changes in signaling involving nuclear factor kappa-light-chain-enhancer of activated B cells.

RESULTS

Following treatment with 1,000 pg/mL of p,p'-DDT, we observed an increase in Bax expression, a decrease in Bcl-2 expression, and increases in the expression of caspases 3, 6, and 8. We also noted a rise in the generation of ROS and a reduction in glutathione peroxidase expression after treatment with p,p'-DDT. Additionally, p,p'-DDT treatment led to changes in ER expression and increases in the protein levels of phosphatidylinositol 3-kinase (PI3K), phospho-protein kinase B (phospho-AKT), and phospho-extracellular signal-regulated kinase (phospho-ERK).

CONCLUSION

p,p'-DDT was found to induce apoptosis in human ESCs through oxidative stress and an ER-mediated pathway. The activation of the PI3K/AKT and ERK pathways could represent potential mechanisms by which p,p'-DDT prompts apoptosis in human ESCs and may be linked to endometrial pathologies.

Effects of hazardous chemicals on secondary sex ratio: A comprehensive review

The secondary sex ratio (SSR), defined as the ratio of male to female offspring at birth, has garnered significant scientific interest due to its potential impact on population dynamics and evolution. In recent years, there has been a growing concern regarding the potential consequences of environmental chemicals on the SSR, given their widespread exposure and potential enduring ramifications on the reproductive system. While SSR serves as an indicator of health, ongoing research and scientific inquiry are being conducted to explore the potential relationship between chemicals and offspring ratio. Although some studies have suggested a possible correlation, others have yielded inconclusive results, indicating that the topic is intricate and still needs to be elucidated. The precise mechanism by which chemical agents exert their influence on the SSR remains ambiguous, with disruption of the endocrine system being a prominent justification. In light of the complex interplay between chemical exposure and SSR, the present review aims to comprehensively examine and synthesize existing scientific literature to gain a deeper understanding of how specific chemical exposures may impact SSR. Insights into chemical hazards that shift SSR patterns or trends could guide prevention strategies, including legislative bans of certain chemicals, to minimize environmental and public health risks.

The epoxiconazole and tebuconazole fungicides impair granulosa cells functions partly through the aryl hydrocarbon receptor (AHR) signalling with contrasted effects in obese, normo-weight and polycystic ovarian syndrome (PCOS) patients

Polycystic ovarian syndrome (PCOS), frequently associated to obesity, is the main reproductive disorder in women in age to procreate. Some evidence suggests that pesticides can result in alterations of the female reproductive system, including polycystic ovary syndrome (PCOS). Here, we detected two fungicides, Tebuconazole (Tb) and Epoxiconazole (Epox) in the soils and waters of French area. Our hypothesis is that these two triazoles could be associated to the etiology of PCOS. We used the human KGN cell line and primary human granulosa cells (hGCs) from different group of patients: normal weight non PCOS (NW), normal weight PCOS (PCOS NW), obese (obese) and obese PCOS (PCOS obese). We exposed in vitro these cells to Tb and Epox from 0 up to 10 mM for 24 and 48 h and analysed cell viability and steroidogenesis. In hGCs NW, cell viability was reduced from 12.5 µM for Tb and 75 µM for Epox. In hGCs NW, Epox decreased progesterone (Pg) and estradiol (E2) secretions and inhibited STAR, HSD3B and CYP19A1 mRNA expressions from 25 µM and increased AHR mRNA expression from 75 µM. Tb exposure also reduced steroid secretion and STAR and CYP19A1 mRNA expressions and increased AHR mRNA expression but at cytotoxic concentrations. Silencing of AHR in KGN cells reduced inhibitory effects of Tb and Epox on steroid secretion. Tb and Epox exposure decreased more steroid secretion in hGCs from obese, PCOS NW and PCOS obese groups than in NW group. Moreover, we found a higher gene expression of AHR within these three groups. Taken together, both Epox and Tb reduced steroidogenesis in hGCs through partly AHR and Tb was more cytotoxic than Epox. These triazoles alter more strongly PCOS and/or obese hGCs suggesting that human with reproductive disorders are more sensitive to triazoles exposure.

Environmental health hazards of untreated livestock wastewater: potential risks and future perspectives

Due to technological and economic limitations, waste products such as sewage and manure generated in livestock farming lack comprehensive scientific and centralized treatment. This leads to the exposure of various contaminants in livestock wastewater, posing potential risks to both the ecological environment and human health. This review evaluates the environmental and physical health risks posed by common pollutants in livestock wastewater and outlines future treatment methods to mitigate these risks. Residual wastes in livestock wastewater, including pathogenic bacteria and parasites surviving after epidemics or diseases on various farms, along with antibiotics, organic wastes, and heavy metals from farming activities, contribute to environmental damage and pose risks to human health. As the livestock industry's development increasingly impacts society's future negatively, addressing the issue of residual wastes in livestock wastewater discharge becomes imperative. Ongoing advancements in wastewater treatment systems are consistently updating and refining practices to effectively minimize waste exposure at the discharge source, mitigating risks to environmental ecology and human health. This review not only summarizes the "potential risks of livestock wastewater" but also explores "the prospects for the development of wastewater treatment technologies" based on current reports. It offers valuable insights to support the long-term and healthy development of the livestock industry and contribute to the sustainable development of the ecological environment.

[Influence of adherence to a mediterranean diet and nutritional status on ovarian reserve]

OBJECTIVE

Currently, esterility affects between 15% and 20% of couples of fertile age. Female reproductive success is mainly determined by age and ovarian reserve (OR). Recent studies highlight the influence of modifiable factors such as dietary habits and nutritional status on OR. In this regard, the Mediterranean Diet (MD) is postulated as a standard of healthy eating. Therefore, the objective of this paper was to analyze the influence of adherence to DM and nutritional status on the OR of infertile women.

METHODS

A descriptive cross-sectional study was carried out, lasting one year, between February 2022 and February 2023, in a sample of forty-five female patients who attended the Gynaecology-Esterility consultation at the Marina Salud Hospital in Denia (Spain) due to genital desire older than one year. An exploratory descriptive analysis based on univariate statistics was performed.

RESULTS

The mean age of the sample (n=45) was 31.84 (±3.99) years, with an average BMI of 26.27 (±6.08) kg/m2, with 44.4% (n=20) having excess body weight. The RO was measured based on AMH, with an average value of 2.32 (±1.59) ng/ml and RFA, with an average of 19.80 (±14.13) antral follicles. A statistically significant association was found between low adherence to DM and lower anti-Müllerian hormone (AMH; p=0.025) levels. In addition, an association was found between low consumption of vegetables (p=0.044), excessive consumption of red meat (p=0.027) and carbonated beverages (p=0.015) with insufficient AMH levels, indicative of low OR. Low fruit consumption was also found to be associated with low oestradiol levels (p=0.045). Statistically significant associations were also found reflecting the influence of nutritional status on OR.

CONCLUSIONS

One of the main factors conditioning the success of ART (assisted reproductive technology) is the woman's OR. The most widely used parameter to assess OR is AMH. Lifestyle and diet are modifiable factors that can influence OR. High adherence to DM and consumption of vegetables is associated with higher levels of AMH; however, high intake of red meat and carbonated beverages is associated with lower levels. Nutritional status, adherence to DM and dietary habits influence the status of OR, so it would be advisable to promote programmes to improve the population's diet in order to improve reproductive health.

Bisphenol A triggers apoptosis in mouse pre-antral follicle granulosa cells via oxidative stress

BACKGROUND

Bisphenol A (BPA), an endocrine disrupting chemical with weak estrogenic and anti-androgenic activity, is widely present in various environmental media and organisms. It has certain reproductive toxicity and can cause a variety of female reproductive system diseases. Although BPA-stimulated apoptosis of granulosa cells has been widely elaborated, the effect of BPA on mouse pre-antral follicle granulosa cells (mpGCs) has not been well elucidated.

RESULTS

In this study, the results of live-dead cell staining showed that high concentrations of BPA severely impaired mpGCs growth viability and affected the cell cycle transition of mpGCs. We confirmed that BPA promotes the production of reactive oxygen species (ROS) and facilitates oxidative stress in mpGCs. In addition, immunofluorescence, transmission electron microscopy, and flow cytometry experiments demonstrated that BPA treatment for mpGCs resulted in apoptotic features, such as rounding, cytoplasmic crinkling, and mitochondrial damage. This was accompanied by a large production of ROS and apoptosis-inducing factor (AIF) translocation from the mitochondria to the nucleus. RNA-seq data showed that several apoptosis-related pathways were enriched in the high concentration BPA-treated group compared with the normal group, such as the p53 pathway, MAPK pathway, etc. CONCLUSIONS: These results suggest that cells undergo oxidative stress effects and apoptosis after BPA treatment for mpGCs, which affects normal follicle development. The potential mechanism of BPA-induced female reproductive toxicity was elucidated, while providing a research basis for the prevention and treatment of female reproductive diseases.

Exploring the potential mechanism of atrazine-induced dopaminergic neurotoxicity based on integration strategy

BACKGROUND

Atrazine (ATR), a commonly used herbicide, is linked to dopaminergic neurotoxicity, which may cause symptoms resembling Parkinson's disease (PD). This study aims to reveal the molecular regulatory networks responsible for ATR exposure and its effects on dopaminergic neurotoxicity based on an integration strategy.

METHODS

Our approach involved network toxicology, construction of protein-protein interaction (PPI) networks, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, as well as molecular docking techniques. Subsequently, we validated the predicted results in PC12 cells in vitro.

RESULTS

An integrated analysis strategy indicating that 5 hub targets, including mitogen-activated protein kinase 3 (Mapk3), catalase (Cat), heme oxygenase 1 (Hmox1), tumor protein p53 (Tp53), and prostaglandin-endoperoxide synthase 2 (Ptgs2), may play a crucial role in ATR-induced dopaminergic injury. Molecular docking indicated that the 5 hub targets exhibited certain binding activity with ATR. Cell counting kit-8 (CCK8) results illustrated a dose-response relationship in PC12 cells. Real-time quantitative polymerase chain reaction (RT-qPCR) displayed notable changes in the expression of hub targets mRNA levels, with the exception of Mapk3. Western blotting results suggested that ATR treatment in PC12 cells resulted in an upregulation of the Cat, Hmox1, and p-Mapk3 protein expression levels while causing a downregulation in Tp53, Ptgs2, and Mapk3.

CONCLUSION

Our findings indicated that 5 hub targets identified could play a vital role in ATR-induced dopaminergic neurotoxicity in PC12 cells. These results provide preliminary support for further investigation into the molecular mechanism of ATR-induced toxicity.

The Gut Microbiota: a Novel Player in the Pathogenesis of Uterine Fibroids

Uterine fibroid is a common gynecological disorder that affects women of reproductive age and has emerged as a major public health concern. The symptoms have a negative influence on both their physical health and quality of life. The cost of treatment has a significant impact on the disease's burden. Even though its origin is uncertain, estrogen is thought to be a key player in fibroid pathophysiology. Many theories, including those based on genetic and environmental factors, explain what causes hyper-estrogenic condition in fibroid patients. One such possibility that is currently being explored is the hypothesis that an altered gut microbiome can contribute to the development of diseases characterized by estrogen dominance. Gut dysbiosis is often a "hot area" in the health sciences. According to a recent study, uterine fibroid patients have altered gut microbiome. A variety of risk factors influence both fibroid development and gut homeostasis. Diet, lifestyle, physical activity, and environmental contaminants have an impact on estrogen and the gut flora. A better understanding of uterine fibroids' pathophysiology is required to develop effective preventative and treatment options. A few ways by which the gut microbiota contributes to UF include estrogen, impaired immune function, inflammation, and altered gut metabolites. Therefore, in the future, while treating fibroid patients, various strategies to deal with changes in the gut flora may be advantageous. For developing suggestions for clinical diagnosis and therapy, we reviewed the literature on the relationship between uterine fibroids and the gut microbiota.

Personal Care and Household Cleaning Product Use among Pregnant Women and New Mothers during the COVID-19 Pandemic

This study examined product use among pregnant women and new mothers in New York City during the COVID-19 pandemic (July 2020-June 2021). Women reported use of personal care and household cleaning products within the previous month, changes in antibacterial product use, receipt of healthcare provider advice, and opinions on environmental chemicals (n = 320). On average, women used 15 personal care products and 7 household cleaning products. Non-Hispanic Black women used nearly two more personal care products; non-Hispanic Black women, those with a college degree, and essential workers used 1-3 more household cleaning products. Women who were Hispanic or reported their race and ethnicity as Other were two times more likely to use antibacterial personal care products. Non-Hispanic Black, Hispanic, and women who reported their race and ethnicity as Other were 1.5 times more likely to increase antibacterial product use during the pandemic. Nearly all women agreed that environmental chemicals pose health risks and are impossible to avoid, while less than one quarter received advice regarding product use. Product use is a modifiable source of chemical exposures. Results from this study suggest that women may have increased their product use during the pandemic. Healthcare providers may use the current focus on health hygiene to promote discussion and assessment of environmental chemical exposures with patients.

The effects of polycyclic aromatic compounds (PACs) on mammalian ovarian function

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Toxicity of polycyclic aromatic compounds (PACs) is limited to a subset of PACs.

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Exposure to these compounds impact major processes necessary for ovarian function.

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PAC exposure causes follicle loss and aberrant steroid production and angiogenesis.

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PAC exposure may increase the risk for impaired fertility and ovarian pathologies.

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The study of PACs as ovarian toxicants should include additional compounds.

Polycyclic aromatic compounds (PACs) are a broad class of contaminants ubiquitously present in the environment due to natural and anthropogenic activities. With increasing industrialization and reliance on petroleum worldwide, PACs are increasingly being detected in different environmental compartments. Previous studies have shown that PACs possess endocrine disruptive properties as these compounds often interfere with hormone signaling and function. In females, the ovary is largely responsible for regulating reproductive and endocrine function and thus, serves as a primary target for PAC-mediated toxicity. Perturbations in the signaling pathways that mediate ovarian folliculogenesis, steroidogenesis and angiogenesis can lead to adverse reproductive outcomes including polycystic ovary syndrome, premature ovarian insufficiency, and infertility. To date, the impact of PACs on ovarian function has focused predominantly on polycyclic aromatic hydrocarbons like benzo(a)pyrene, 3-methylcholanthrene and 7,12-dimethylbenz[a]anthracene. However, investigation into the impact of substituted PACs including halogenated, heterocyclic, and alkylated PACs on mammalian reproduction has been largely overlooked despite the fact that these compounds are found in higher abundance in free-ranging wildlife. This review aims to discuss current literature on the effects of PACs on the ovary in mammals, with a particular focus on folliculogenesis, steroidogenesis and angiogenesis, which are key processes necessary for proper ovarian functions.

Polycystic Ovary Syndrome: An Evolutionary Adaptation to Lifestyle and the Environment

Polycystic ovary syndrome (PCOS) is increasingly recognized as a complex metabolic disorder that manifests in genetically susceptible women following a range of negative exposures to nutritional and environmental factors related to contemporary lifestyle. The hypothesis that PCOS phenotypes are derived from a mismatch between ancient genetic survival mechanisms and modern lifestyle practices is supported by a diversity of research findings. The proposed evolutionary model of the pathogenesis of PCOS incorporates evidence related to evolutionary theory, genetic studies, in utero developmental epigenetic programming, transgenerational inheritance, metabolic features including insulin resistance, obesity and the apparent paradox of lean phenotypes, reproductive effects and subfertility, the impact of the microbiome and dysbiosis, endocrine-disrupting chemical exposure, and the influence of lifestyle factors such as poor-quality diet and physical inactivity. Based on these premises, the diverse lines of research are synthesized into a composite evolutionary model of the pathogenesis of PCOS. It is hoped that this model will assist clinicians and patients to understand the importance of lifestyle interventions in the prevention and management of PCOS and provide a conceptual framework for future research. It is appreciated that this theory represents a synthesis of the current evidence and that it is expected to evolve and change over time.

Perfluoroalkyl substances (PFAS) in drinking water and risk for polycystic ovarian syndrome, uterine leiomyoma, and endometriosis: A Swedish cohort study

BACKGROUND

Perfluorinated substances (PFAS) are chemicals with endocrine disruptive properties that may interfere with the female reproductive system. However, few studies have explored the association between benign gynecological diseases and high PFAS exposure.

OBJECTIVES

The aim of this study was to investigate the possible associations between PFAS exposure and subsequent diagnosis of polycystic ovarian syndrome (PCOS), uterine leiomyoma (fibroids), and endometriosis in a cohort exposed to PFAS through drinking water.

MATERIAL AND METHODS

In 2013, high levels (with sum of PFAS above 10,000 ng/L), dominated by perfluorooctanesulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS), were found in the drinking water from one of the two waterworks in Ronneby, Sweden. The contamination came from firefighting foams used at a nearby airfield. Females of all ages (n = 29,106) who had ever resided in the municipality between 1985 and 2013 formed a cohort. Individual exposure was assessed based on municipality waterworks distribution data linked to annual residential address data; 27% of the females had ever lived at an address with PFAS-contaminated water. Gynecological health outcomes were retrieved from the Swedish National Patient Register. The Cox proportional hazards model was used to estimate the association between exposure and each diagnosis.

RESULTS

There were in all 161 cases of PCOS, 1,122 cases of uterine leiomyoma, and 373 cases of endometriosis. In women aged 20-50 years (n = 18,503), those with the highest estimated PFAS exposure had increased hazard ratios (HR) for PCOS (HR = 2.18; 95% confidence interval (CI) 1.43, 3.34) and uterine leiomyoma (HR = 1.28; 95% CI 0.95, 1.74). No increased HR for endometriosis was found (HR = 0.74; 95% CI 0.42, 1.29).

CONCLUSIONS

Exposure to high levels of PFAS in drinking water was associated with increased risk of PCOS and possibly uterine leiomyoma, but not endometriosis. The findings for PCOS are consistent with prior studies reporting positive associations between PCOS and PFAS exposure at background levels.

Meta-analysis and experimental validation identified atrazine as a toxicant in the male reproductive system

Atrazine (ATZ), as a widely used triazine herbicide, is an environmental endocrine disruptor (EDC) that can cause many health problems. Therefore, we conducted this study based on the evidence of rats and mice to figure out the characteristics of ATZ damage to the reproductive system and further evaluate its health effects on the human. PRISMA's guidelines were followed according to the principles recommended by the Cochrane Handbook for Systematic Review. Health assessment was performed using the OHAT approach. Our new data were obtained from randomized controlled trials in rats designed in accordance with toxicological guidelines. Exposure to ATZ was significantly associated with decreased testosterone production (SMD = - 0.90, 95% CI - 1.27 to - 0.53), and reduced absolute weights of testis (SMD = - 0.41, 95% CI - 0.61 to - 0.22) and other reproductive organs. The damaging effect of sperm quality was also observed clearly, which included reduction of sperm count both in epididymis (SMD = - 2.32, 95% CI - 2.83 to - 1.81) and testis (SMD = - 1.01, 95% CI - 1.37 to - 0.64), decrease in sperm motility (SMD = - 8.86, 95% CI - 10.88 to - 6.83), and increase in sperm abnormality. Subgroup analysis revealed consistency across different species, life stage, and dosage. In addition, we found that ATZ exposure at a daily dose of 120 mg/kg during adolescence could cause decrease in weight gain and histological damage to the testis. The gene expression levels of Nrf2/HO-1 and Bcl-2/caspase signaling pathways in testis tissues were changed significantly. The results of this SR indicated that exposure to ATZ was associated with impairment of male reproductive system in rodents regardless of species, exposure life stage, and dosage. It is believed that ATZ exposure may have similar effects on male reproductive system of human beings. Pathways related to oxidative stress and apoptosis may be the mechanism leading to testicular damage in rats treated with ATZ.

Reproductive Health Risks Associated with Occupational and Environmental Exposure to Pesticides

A marked reduction in fertility and an increase in adverse reproductive outcomes during the last few decades have been associated with occupational and environmental chemical exposures. Exposure to different types of pesticides may increase the risks of chronic diseases, such as diabetes, cancer, and neurodegenerative disease, but also of reduced fertility and birth defects. Both occupational and environmental exposures to pesticides are important, as many are endocrine disruptors, which means that even very low-dose exposure levels may have measurable biological effects. The aim of this review was to summarize the knowledge collected between 2000 and 2020, to highlight new findings, and to further interpret the mechanisms that may associate pesticides with infertility, abnormal sexual maturation, and pregnancy complications associated with occupational, environmental and transplacental exposures. A summary of current pesticide production and usage legislation is also included in order to elucidate the potential impact on exposure profile differences between countries, which may inform prevention measures. Recommendations for the medical surveillance of occupationally exposed populations, which should be facilitated by the biomonitoring of reduced fertility, is also discussed.

The Association of Bisphenol A and Phthalates with Risk of Breast Cancer: A Meta-Analysis

Background: Breast cancer is the most common cancer and the second leading cause of cancer-related death amongst American women. Endocrine-disrupting chemicals (EDCs), especially bisphenol A (BPA) and phthalates, have adverse effects on human health. However, the association of BPA and phthalates with breast cancer remains conflicting. This study aims to investigate the association of BPA and phthalates with breast cancer. Methods: Correlative studies were identified by systematically searching three electronic databases, namely, PubMed, Web of Sciences, and Embase, up to November 2020. All data were analyzed using Stata 15.0. Results: A total of nine studies, consisting of 7820 breast cancer cases and controls, were included. The urinary phthalate metabolite mono-benzyl phthalate (MBzP) and mono-2-isobutyl phthalate (MiBP) were negatively associated with breast cancer (OR = 0.73, 95% CI: 0.60–0.90; OR = 0.75, 95% CI: 0.58–0.98, respectively). However, the overall ORs for BPA, mono-ethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-(3-carboxypropyl) phthalate (MCPP), and mono-butyl phthalate (MBP) were 0.85 (95% CI: 0.69–1.05), 0.96 (95% CI: 0.62–1.48), 1.12 (95% CI: 0.88–1.42), 1.13 (95% CI: 0.74–1.73), 1.01 (95% CI: 0.74–1.40), 0.74 (95% CI: 0.48–1.14), and 0.80 (95% CI: 0.55–1.15), respectively, suggesting no significant association. The sensitivity analysis indicated that the results were relatively stable. Conclusion: Phthalate metabolites MBzP and MiBP were passively associated with breast cancer, whereas no associations were found between BPA, MEP, MEHHP, MEHP, MEOHP, MCPP, and MBP and breast cancer. More high-quality case-control studies or persuasive cohort studies are urgently needed to draw the best conclusions.

Evaluation of Gonadal Alterations in a Population Environmentally Exposed to a Mixture of Endocrine Active Pesticides

Although there are studies that show that some pesticides produce gonadal dysfunction and gonadal cancer in different animals, there are not many studiesregardinghumans. This study determined the prevalence and risk in humans of developing ovarian or testicular dysfunction or cancer in areas with distinct exposure to pesticides, which have endocrine disrupting properties. A population-based case-control study was carried out on humans living in ten health districts of Andalusia (Southern Spain) classified as areas of high or low environmental exposure to pesticides according to agronomic criteria. The study population included 5332 cases and 13,606 controls. Data were collected from computerized hospital records between 2000 and 2018.The risk of gonadal dysfunction or cancer was significantly higher in areas with higher use of pesticides in relation to those with lower use.

Effects of Phthalate Esters on Human Myometrial and Fibroid Cells: Cell Culture and NOD-SCID Mouse Data

Evidence is growing that phthalate esters play an important role in the pathogenesis of estrogen-dependent gynecologic diseases, especially uterine fibroids. We aimed to investigate whether in vitro treatment with di-(2-ethylhexyl)-phthalate (DEHP) affects angiogenesis, proliferation, and apoptosis in uterine fibroids. To ascertain this, we evaluated vascular endothelial growth factor (VEGF) expression and AKT/ERT phosphorylation and compared the fibroid volume between nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice fed with and without DEHP. VEGF expression was measured using enzyme-linked immunosorbent assay, and AKT/ERK phosphorylation was analyzed by western blot analysis in human myometrial and fibroid cells. The volume of the fibroid tissues implanted to NOD/SCID mice was measured, and the expression of collagen type I protein, Ki-67, proliferating cell nuclear antigen, and B cell lymphoma 2 were analyzed using immunohistochemistry. We could see significant increases in VEGF expression and AKT phosphorylation in human myometrial and fibroid cells treated with DEHP. The volume of the fibroid tissues was significantly increased in NOD/SCID mice fed with DEHP, which was accompanied by increased expression of collagen type I and AKT phosphorylation. Taken together, these results suggest that exposure to phthalate esters may influence uterine fibroid pathogenesis by increasing VEGF and collagen expression and upregulating AKT phosphorylation.

The effect of the pesticide delivery method on the microbial community of field soil

The study deals with the effects of herbicides (metribuzin, tribenuron-methyl, fenoxaprop-P-ethyl) and fungicides (tebuconazole, epoxiconazole, azoxystrobin) applied to soil as free pesticides or as slow release formulations embedded in a biodegradable composite matrix on the structure of the soil microbial community. The matrix consisted of a natural biopolymer poly-3-hydroxybutyrate [P(3HB)] and a filler-one of the natural materials (peat, clay, and wood flour). The soil microbial community was characterized, including the major eco-trophic groups of bacteria, dominant taxa of bacteria and fungi, and primary P(3HB)-degrading microorganisms, such as Pseudomonas, Bacillus, Pseudarthrobacter, Streptomyces, Penicillium, and Talaromyces. The addition of free pesticides adversely affected the abundance of soil microorganisms; the decrease varied from 1.4 to 56.0 times for different types of pesticides. The slow release pesticide formulations, in contrast to the free pesticides, exerted a much weaker effect on soil microorganisms, no significant inhibition in the abundance of saprotrophic bacteria was observed, partly due to the positive effects of the composite matrix (polymer/natural material), which was a supplementary substrate for microorganisms. The slow release fungicide formulations, like the free fungicides, reduced the total abundance of fungi and inhibited the development of the phytopathogens Fusarium and Alternaria. Thus, slow release formulations of pesticides preserve the bioremediation potential of soil microorganisms, which are the main factor of removing xenobiotics from the biosphere.

Uterine Fibroids and Diet

Uterine myomas or fibroids are the most common benign female tumors of the reproductive organs, associated with significant morbidity and quality of life impairment. Several epidemiological risk factors for their occurrence have been identified so far, including nutrition and dietary habits. In this investigation, authors reviewed, as a narrative review, the data about diet and uterine myoma development in order to homogenize the current data. A PubMed search was conducted for the years 1990–2020, using a combination of keywords of interest for the selected topic. The authors searched the databases, selecting the randomized clinical studies, the observational studies, and the basic (experimental), clinical, and epidemiological researches. Once they collected the articles, they analyzed them according to the number of citations of each article, starting from the most cited to the least cited articles. Subsequently, authors collected the data of each article and inserted them in the various research paragraphs, summarizing the data collected. In this way, they crossed the available data regarding the association between nutrition habits and dietary components and myoma onset and growth. Many nutrients and dietary habits are associated with myoma development risk. These factors include low intakes of fruit, vegetables, and vitamin D, as well as pollutants in food. Despite the available data on the influence of some foods on the development of fibroids, further research is mandatory to understand all the nutrition risk factors which contribute to myoma growth and how exactly these risk factors influence myoma pathogenesis.

From Environmental to Possible Occupational Exposure to Risk Factors: What Role Do They Play in the Etiology of Endometriosis?

Endometriosis is a gynecological disorder characterized by the presence of endometrial stroma and glands outside the uterine cavity. A systematic review of the literature was conducted to clarify, starting from environmental exposure data, whether possible occupational risk factors may correlate with the onset of the disease. The guidelines for reporting systematic reviews of the “PRISMA” statement were followed and two databases, Scopus and PubMed, were used. Of the 422 studies selected with specific keywords, 32 publications were eligible, 28 of which referred to chemical agents and 4 related to night work. Conflicting data emerged among these studies. Although some compounds seemed to be more involved than others in the onset of endometriosis. Association with exposure to organochlorine compounds is the most supported by the epidemiological data, while other pesticide exposure did not show any clear correlation. Likewise, the hypothesis of a correlation with perfluoroalkyls exposure is not currently supported by data. The involvement of metals as risk factors has not been confirmed, while the role of night work, in the case of long service, seems to play an etiological role. In order to clarify the potential occupational risk of endometriosis development, well-designed studies are needed to evaluate the potential association between chemical compounds and disease etiology.

Hypothetical roadmap towards endometriosis: prenatal endocrine-disrupting chemical pollutant exposure, anogenital distance, gut-genital microbiota and subclinical infections

BACKGROUND

Endometriosis is a gynaecological hormone-dependent disorder that is defined by histological lesions generated by the growth of endometrial-like tissue out of the uterus cavity, most commonly engrafted within the peritoneal cavity, although these lesions can also be located in distant organs. Endometriosis affects ~10% of women of reproductive age, frequently producing severe and, sometimes, incapacitating symptoms, including chronic pelvic pain, dysmenorrhea and dyspareunia, among others. Furthermore, endometriosis causes infertility in ~30% of affected women. Despite intense research on the mechanisms involved in the initial development and later progression of endometriosis, many questions remain unanswered and its aetiology remains unknown. Recent studies have demonstrated the critical role played by the relationship between the microbiome and mucosal immunology in preventing sexually transmitted diseases (HIV), infertility and several gynaecologic diseases.

OBJECTIVE AND RATIONALE

In this review, we sought to respond to the main research question related to the aetiology of endometriosis. We provide a model pointing out several risk factors that could explain the development of endometriosis. The hypothesis arises from bringing together current findings from large distinct areas, linking high prenatal exposure to environmental endocrine-disrupting chemicals with a short anogenital distance, female genital tract contamination with the faecal microbiota and the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis.

SEARCH METHODS

We performed a search of the scientific literature published until 2019 in the PubMed database. The search strategy included the following keywords in various combinations: endometriosis, anogenital distance, chemical pollutants, endocrine-disrupting chemicals, prenatal exposure to endocrine-disrupting chemicals, the microbiome of the female reproductive tract, microbiota and genital tract, bacterial vaginosis, endometritis, oestrogens and microbiota and microbiota-immune system interactions.

OUTCOMES

On searching the corresponding bibliography, we found frequent associations between environmental endocrine-disrupting chemicals and endometriosis risk. Likewise, recent evidence and hypotheses have suggested the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis. Hence, we can envisage a direct relationship between higher prenatal exposure to oestrogens or estrogenic endocrine-disrupting compounds (phthalates, bisphenols, organochlorine pesticides and others) and a shorter anogenital distance, which could favour frequent postnatal episodes of faecal microbiota contamination of the vulva and vagina, producing cervicovaginal microbiota dysbiosis. This relationship would disrupt local antimicrobial defences, subverting the homeostasis state and inducing a subclinical inflammatory response that could evolve into a sustained immune dysregulation, closing the vicious cycle responsible for the development of endometriosis.

WIDER IMPLICATIONS

Determining the aetiology of endometriosis is a challenging issue. Posing a new hypothesis on this subject provides the initial tool necessary to design future experimental, clinical and epidemiological research that could allow for a better understanding of the origin of this disease. Furthermore, advances in the understanding of its aetiology would allow the identification of new therapeutics and preventive actions.

Placental Trophoblast-Inspired Lipid Bilayers for Cell-Free Investigation of Molecular Interactions

The placenta plays a key role in regulating the maternal-fetal transport but it is a difficult organ to study due to a lack of existing in vitro models. Lipid bilayers inspired by the placenta can provide a facile new in vitro tool with promise for screening molecular transport across this important organ. Here we developed lipid bilayers that mimic the composition of human placental trophoblast cells at different times during the course of pregnancy. Mass spectrometry identified five major lipid classes (phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, and sphingomyelin) present at varying concentrations in trophoblasts representative of the first and third trimesters and full-term placenta. We successfully developed supported and suspended lipid bilayers mimicking these trophoblast lipid compositions and then demonstrated the utility of these synthetic placenta models for investigating molecular interactions. Specifically, we investigated the interactions with di(2-ethylhexyl) phthalate (DEHP), a common plasticizer and environmental toxicant, and amphotericin B, a common yet toxic, antifungal therapeutic. Overall, we observed that DEHP adsorbs and potentially embeds itself within all placental lipid bilayers, with varying levels of interaction. For both amphotericin B and a liposomal formulation of amphotericin B, AmBisome, we noted lower levels of permeation in transport studies with bilayers and trophoblast cells compared with DEHP, likely driven by differences in size. AmBisome interacted less with both the supported and suspended placental lipid bilayers in comparison to amphotericin B, suggesting that drug delivery carriers can vary the impact of a pharmaceutical agent on these lipid structures. We found that the apparent permeability observed in suspended bilayers was approximately an order of magnitude less than those observed for trophoblast monolayers, which is typical of lipid bilayers. Ultimately, these placenta mimetic lipid bilayers can serve as a platform for the rapid initial screening of molecular interactions with the maternal-fetal interface to better inform future testing.