Quantification of benzo[a]pyrene and other PAHs in the serum and follicular fluid of smokers versus non-smokers

An In Vitro test battery using human whole blood for immunotoxicity hazard identification: Proof of concept studies with dexamethasone and benzo(a)pyrene

Immunotoxicity assessment is nearing a crossroads predicated on mounting pressure for reduction/replacement of animals in toxicology. This has fueled the development of alternative New Approach Methodologies (NAMs) for hazard identification. This work details a comprehensive human whole blood NAM battery for immunotoxicity testing. The test system is a closed tube culture containing whole blood diluted 1:3 in culture media with or without an immune stimulant, anti-CD3/CD28 or viral peptide pool. Model immunotoxicants dexamethasone (DEX; 0 - 1.94 μM) and benzo(a)pyrene [B(a)P; 0-6.3 μM], were added to the test system for 24 hours. Immune cells were identified and counted by flow cytometric immunophenotyping and assessed for natural killer (NK) cell activity and T cell activation. Supernatants were interrogated for proinflammatory cytokine concentrations. In vitro treatment with DEX resulted in concentration-dependent suppression of cytokine production, NK cell activity, and T cell activation induced by anti-CD3/CD28, as well as viral-induced cytokine production. B(a)P caused suppression of cytokine production and a nonsignificant reduction in T cell activation but did not impact NK cell activity, however, immunosuppression by B(a)P only occurred following metabolic activation by S9 fraction enzymes. Advantages of this NAM battery include assessment of adaptive immunity and direct translation of immunotoxicity to viral host resistance. These results provide evidence of in vitro immunotoxicity that reflect known outcomes from in vivo studies. This multi-endpoint human whole blood NAM battery should be useful for screening compounds for immunotoxicity hazard identification without reliance on animal systems for increased translatability to humans.

Polycyclic Aromatic Hydrocarbons (PAHs) in the Environment: Occupational Exposure, Health Risks and Fertility Implications

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds with fused aromatic rings, primarily derived from combustion processes and environmental pollutants. This narrative review discusses the most relevant studies on PAHs, focusing on their sources, environmental and occupational exposure, and effects on human health, emphasizing their roles as carcinogenic, mutagenic, and teratogenic agents. The primary pathways for human exposure to PAHs are through the ingestion of contaminated food (mainly due to some food processing methods, such as smoking and high-temperature cooking techniques), the inhalation of ambient air, and the smoking of cigarettes. Coke oven workers are recognized as a high-risk occupational group for PAH exposure, highlighting the need for appropriate strategies to mitigate these risks and safeguard worker health. PAHs are metabolized into reactive intermediates in the body, which can lead to DNA damage and promote the development of various health conditions, particularly in environments with high exposure levels. Chronic PAH exposure has been linked to respiratory diseases, as well as cardiovascular problems and immune system suppression. Furthermore, this review underscores the significant impact of PAHs on reproductive health. The results of the reported studies suggest that both male and female fertility can be compromised due to oxidative stress, DNA damage, and endocrine disruption caused by PAH exposure. In males, PAHs impair sperm quality, while, in females, they disrupt ovarian function, potentially leading to infertility, miscarriage, and birth defects. Fetal exposure to PAHs is also associated with neurodevelopmental disorders. Given the extensive and detrimental health risks posed by PAHs, this review stresses the importance of stringent environmental regulations, occupational safety measures, and public health initiatives to mitigate exposure and safeguard reproductive and overall health.

Polycyclic aromatic hydrocarbons in human granulosa cells: first in vivo presence and positive correlation with body mass index and in vitro ovarian cell steroidogenesis regulation

Polycyclic Aromatic Hydrocarbons (PAHs) exposure leads to disorders reported in female infertility patients. Our hypothesis is that PAHs accumulate in granulosa cells (Gc) according to body mass index (BMI) and directly affects its functions. All 16 high-priority PAHs were in human FF, Gc and blood plasma with the highest concentration in Gc (GC-MS/MS). Their highest concentration was in obese Gc, except for acenaphthene and acenaphthylene, and positively correlated with BMI. In FF, we noted only positive correlation between naphthalene and BMI, whereas in blood plasma positive correlation between naphthalene, acenaphthene, pyrene and BMI. Phenanthrene and naphthalene but not fluoranthene inhibited totally steroidogenesis (ELISA), CYP19A1 mRNA expression (real-time PCR) and increased oxidative stress index and catalase expression in Gc independently on BMI. While all studied PAHs decreased Gc proliferation (BrdU assay) and viability (Cell Count kit-8 assay). Thus, Gc PAHs concentrations are positively correlated with BMI and alter ovarian functions.

B(a)P induces ovarian granulosa cell apoptosis via TRAF2-NFκB-Caspase1 axis during early pregnancy

Benzo(a)pyrene [B(a)P] is an environmental endocrine disruptor with reproductive toxicity. The corpus luteum (CL) of the ovary plays an important role in embryo implantation and pregnancy maintenance. Our previous studies have shown that B(a)P exposure affects embryo implantation and endometrial decidualization in mouse, but its effects and mechanisms on CL function remain unclear. In this study, we explore the mechanism of ovarian toxicity of B(a)P using a pregnant mouse model and an in vitro model of human ovarian granulosa cells (GCs) KGN. Pregnant mice were gavaged with corn oil or 0.2 mg/kg.bw B(a)P from pregnant day 1 (D1) to D7, while KGN cells were treated with DMSO, 1.0IU/mL hCG, or 1.0IU/mL hCG plus benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), a B(a)P metabolite. Our findings revealed that B(a)P exposure damaged embryo implantation and reduced estrogen and progesterone levels in early pregnant mice. Additionally, in vitro, BPDE impaired luteinization in KGN cells. We observed that B(a)P/BPDE promoted oxidative stress (OS) and inflammation, leading to apoptosis rather than pyroptosis in ovaries and luteinized KGN cells. This apoptotic response was mediated by the activation of inflammatory Caspase1 through the cleavage of BID. Furthermore, B(a)P/BPDE inhibited TRAF2 expression and suppressed NFκB signaling pathway activation. The administration of VX-765 to inhibit the Caspase1 activation, over-expression of TRAF2 using TRAF2-pcDNA3.1 (+) plasmid, and BetA-induced activation of NFκB signaling pathway successfully alleviated BPDE-induced apoptosis and cellular dysfunction in luteinized KGN cells. These findings were further confirmed in the KGN cell treated with H2O2 and NAC. In conclusion, this study elucidated that B(a)P/BPDE induces apoptosis rather than pyroptosis in GCs via TRAF2-NFκB-Caspase1 during early pregnancy, and highlighting OS as the primary contributor to B(a)P/BPDE-induced ovarian toxicity. Our results unveil a novel role of TRAF2-NFκB-Caspase1 in B(a)P-induced apoptosis and broaden the understanding of mechanisms underlying unexplained luteal phase deficiency.

Exposure to Polycyclic Aromatic Hydrocarbons and adverse reproductive outcomes in women: current status and future perspectives

OBJECTIVES

Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous, toxic environmental chemicals that can cause adverse reproductive health effects. The objectives of this mini-review are to highlight the adverse reproductive outcomes due to PAH exposure with the main focus on polycystic ovary syndrome (PCOS) and premature ovarian failure (POF) and to provide perspectives on future research needs.

CONTENT

We reviewed studies that have reported the adverse reproductive outcomes associated with PAHs exposures in women through a comprehensive search of bibliographic databases and gray literature sources. In addition, potentially modifiable sources of exposure to PAHs and associated reproductive outcomes were also investigated.

SUMMARY

A total of 232 papers were retrieved through a comprehensive search of bibliographic databases, out of which three studies met the eligibility criteria and were included in the review. Results showed that exposure to PAHs is associated with adverse reproductive outcomes defined as PCOS, POF, and reproductive hormone imbalance. Sources of PAH exposure associated with adverse reproductive outcomes include active and passive tobacco smoking, specific cooking methods, and pesticides.

OUTLOOK

Future studies are warranted to examine the mechanisms by which PAHs result in adverse reproductive endpoints in women. Further, environmental exposures that are potentially modifiable such as exposure to tobacco smoke, may contribute to PAH exposure, and these exposures should be targeted in future policies and interventions.

Consumption of hookahs, e-cigarettes, and classic cigarettes and the impact on medically assisted reproduction treatment

Smoking of classic cigarettes has been well-established as a health risk factor, including cardiovascular, neurological, and pulmonary diseases. Adverse effects on human reproduction have also been shown. Smokers are assumed to have a significantly lower chance of pregnancy, however, the impact of smoking on medically assisted reproduction (MAR) treatment outcomes is controversial. Moreover, smoking habits have changed during the last decades since e-cigarettes and hookahs, or water pipes, have become very popular, yet little is known regarding vaping or hookah-smoking patients undergoing MAR treatments. This prospective study aimed to examine the presence of benzo[a]pyrene, nicotine, and its main metabolite, cotinine, in human follicular fluid (FF) in non-smoking, smoking, and vaping/hookah-smoking patients and to evaluate the impact on female fertility. Human FF samples were collected from 320 women subjected to intracytoplasmic sperm injection (ICSI) cycles due to male subfertility. Gas chromatography combined with mass spectrometry was used to analyse the presence of benzo[a]pyrene, nicotine, and cotinine. A questionnaire was provided to assess patient consumption behaviour and to identify (1) non-smoking patients, (2) patients who consumed cigarettes, and (3) patients with exclusive consumption of e-cigarettes or hookahs. Data were analysed using linear and logistic regression, Fisher's exact test, and the Mann-Whitney U Test. Nicotine was present in 22 (6.8%) and cotinine in 65 (20.3%) of the 320 samples. The nicotine and cotinine concentrations per sample ranged from 0 to 26.3 ng/ml and 0-363.0 ng/ml, respectively. Benzo[a]pyrene was not detectable in any of the samples analysed. Nicotine and cotinine were also present in the FF of patients with exclusive consumption of e-cigarettes or hookahs. The clinical pregnancy rate, fertilization and maturation rates, and number of oocytes per oocyte pick-up were not statistically significantly different between non-smoking, smoking, or vaping/hookah-smoking patients. Smoking and the accumulation of smoking toxins in the FF have no impact on the outcome of MAR treatments-neither the clinical pregnancy rate, maturation and fertilization rates, nor the number of retrieved oocytes were affected. For the first time, nicotine and cotinine were quantified in the FF of patients exclusively vaping e-cigarettes or smoking hookahs. Since vaping liquids and hookah tobaccos contain potentially harmful substances, other adverse effects cannot be excluded.Trial registration ClinicalTrials.gov Identifier: NCT03414567.

Biological sex differences in hepatic response to in utero dimethylbenz(a)anthracene exposure

Fetal hepatic dimethylbenz(a)anthracene (DMBA) biotransformation is not defined, thus, this study investigated whether the fetal liver metabolizes DMBA and differs with biological sex. KK.Cg-a/a (lean; n = 20) or KK.Cg-Ay/J (obese; n = 20) pregnant mice were exposed to corn oil (CT) or DMBA (1 mg/kg bw/day) by intraperitoneal injection (n = 10/treatment) from gestation day 7-14. Postnatal day 2 male or female offspring livers were collected. Total RNA (n = 6) and protein (n = 6) were analyzed via a PCR-based array or LC-MS/MS, respectively. The level of Mgst3 was lower (P < 0.05) in livers of female compared to male offspring. Furthermore, in utero DMBA exposure increased (P < 0.1) Cyp2c29 and Gpx3 levels (P < 0.05) in female offspring. In male offspring, the abundance of Ahr, Comt (P < 0.1), Alox5, and Asna1 (P < 0.05) decreased due to DMBA exposure. Female and male offspring had 34 and 21 hepatic proteins altered (P < 0.05) by in utero DMBA exposure, respectively. Opposing patterns for hepatic CD81 and KRT78 occurred, being decreased in females but increased in males, while YWHAG was decreased by DMBA exposure in both. Functional KEGG pathway analysis identified enrichment of 26 and 13 hepatic metabolic proteins in male and female offspring, respectively, due to in utero DMBA exposure. In silico transcription factor analysis of differentially expressed proteins predicted involvement of female NRF1 but male AHR. Thus, hepatic biological sex differences and capacity to respond to toxicants in utero are supported.

Lipid Peroxidation as the Mechanism Underlying Polycyclic Aromatic Hydrocarbons and Sunlight Synergistic Toxicity in Dermal Fibroblasts

Light and atmospheric pollution are both independently implicated in cancer induction and premature aging. Evidence has been growing more recently on the toxic synergy between light and pollutants. Polycyclic aromatic hydrocarbons (PAHs) originate from the incomplete combustion of organic matter. Some PAHs, such as the Benzo[a]pyrene (BaP), absorb ultraviolet A (UVA) wavelengths and can act as exogenous chromophores, leading to synergistic toxicity through DNA damage and cytotoxicity concomitant to ROS formation. In this study, we shed light on the mechanism underlying the toxic synergy between PAHs and UVA. Using dermal fibroblasts co-exposed to UVA and BaP, we have demonstrated that the photosensitization reaction causes mortality, which is most likely caused by ROS accumulation. We have shown that these ROS are concentrated in the lipids, which causes an important induction of lipid peroxidation and malondialdehyde, by-products of lipid peroxidation. We have also shown the accumulation of bulky DNA damage, most likely generated by these by-products of lipid peroxidation. To our knowledge, this study represents the first one depicting the molecular effects of photo-pollution on dermal skin.

Benzo[a]pyrene disrupts LH/hCG-dependent mouse Leydig cell steroidogenesis through receptor/Gαs protein targeting

Steroidogenesis of gonadal cells is tightly regulated by gonadotropins. However, certain polycyclic aromatic hydrocarbons, including Benzo[a]pyrene (BaP), induce reproductive toxicity. Several existing studies have considered higher than environmentally relevant concentrations of BaP on male and female steroidogenesis following long-term exposure. Also, the impact of short-term exposure to BaP on gonadotropin-stimulated cells is understudied. Therefore, we evaluated the effect of 1 nM and 1 µM BaP on luteinizing hormone/choriogonadotropin (LH/hCG)-mediated signalling in two steroidogenic cell models, i.e. the mouse tumor Leydig cell line mLTC1, and the human primary granulosa lutein cells (hGLC) post 8- and 24-h exposure. Cell signalling studies were performed by homogeneous time-resolved fluorescence (HTRF) assay, bioluminescence energy transfer (BRET) and Western blotting, while immunostainings and immunoassays were used for intracellular protein expression and steroidogenesis analyses, respectively. BaP decreased cAMP production in gonadotropin-stimulated mLTC1 interfering with Gαs activation. Therefore, decrease in gonadotropin-mediated CREB phosphorylation in mLTC1 treated with 1 μM BaP was observed, while StAR protein levels in gonadotropin-stimulated mLTC1 cells were unaffected by BaP. Further, BaP decreased LH- and hCG-mediated progesterone production in mLTC1. Contrastingly, BaP failed to mediate any change in cAMP, genes and proteins of steroidogenic machinery and steroidogenesis of gonadotropin-treated hGLC. Our results indicate that short-term exposure to BaP significantly impairs steroidogenic signalling in mLTC1 interfering with Gαs. These findings could have a significant impact on our understanding of the mechanism of reproductive toxicity by endocrine disruptors.

Indenopyrene and Blue-Light Co-Exposure Impairs the Tightly Controlled Activation of Xenobiotic Metabolism in Retinal Pigment Epithelial Cells: A Mechanism for Synergistic Toxicity

High energy visible (HEV) blue light is an increasing source of concern for visual health. Polycyclic aromatic hydrocarbons (PAH), a group of compounds found in high concentrations in smokers and polluted environments, accumulate in the retinal pigment epithelium (RPE). HEV absorption by indeno [1,2,3-cd]pyrene (IcdP), a common PAH, synergizes their toxicities and promotes degenerative changes in RPE cells comparable to the ones observed in age-related macular degeneration. In this study, we decipher the processes underlying IcdP and HEV synergic toxicity in human RPE cells. We found that IcdP-HEV toxicity is caused by the loss of the tight coupling between the two metabolic phases ensuring IcdP efficient detoxification. Indeed, IcdP/HEV co-exposure induces an overactivation of key actors in phase I metabolism. IcdP/HEV interaction is also associated with a downregulation of proteins involved in phase II. Our data thus indicate that phase II is hindered in response to co-exposure and that it is insufficient to sustain the enhanced phase I induction. This is reflected by an accelerated production of endogenous reactive oxygen species (ROS) and an increased accumulation of IcdP-related bulky DNA damage. Our work raises the prospect that lifestyle and environmental pollution may be significant modulators of HEV toxicity in the retina.

Long-term reproductive effects of benzo(a)pyrene at environmentally relevant dose on juvenile female rats

Since studies on the reproductive consequences after the exposure to environmentally relevant doses of Benzo(a)pyrene (BaP) during critical stages of development are scarce, this study evaluated female reproductive parameters of adult rats exposed to a low dose of BaP during the juvenile phase. Female rats (Post-natal 21) were treated with BaP (0 or 0.1 µg/kg/day; gavage) for 21 consecutive days. During the treatment, no clinical signs of toxicity were observed. Nevertheless, the ages of vaginal opening and first estrus were anticipated by the BaP-exposure. At the sexual maturity, the juvenile exposure compromised the sexual behavior, as well as the placental efficiency, follicle stimulating hormone levels, placenta histological analysis, and ovarian follicle count. A decrease in erythrocyte, platelet, and lymphocyte counts also was observed in the exposed-females. Moreover, the dose of BaP used in this study was not able to produce estrogenic activity in vivo. These data showed that juvenile BaP-exposure, at environmentally relevant dose, compromised the female reproductive system, possibly by an endocrine deregulation; however, this requires further investigation.

BaP/BPDE suppressed endothelial cell angiogenesis to induce miscarriage by promoting MARCHF1/GPX4-mediated ferroptosis

Environmental benzo(a)pyrene (BaP) and its ultimate metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) are universal and inevitable persistent organic pollutants and endocrine disrupting chemicals. Angiogenesis in placental decidua plays a pivotal role in healthy pregnancy. Ferroptosis is a newly identified and iron-dependent cell death mode. However, till now, BaP/BPDE exposure, ferroptosis, defective angiogenesis, and miscarriage have never been correlated; and their regulatory mechanisms have been rarely explored. In this study, we used assays with BPDE-exposed HUVECs (human umbilical vein endothelial cells), decidual tissues and serum samples collected from unexplained recurrent miscarriage and their matched healthy control groups, and placental tissues of BaP-exposed mouse miscarriage model. We found that BaP/BPDE exposure caused ferroptosis and then directly suppressed angiogenesis and eventually induced miscarriage. In mechanism, BaP/BPDE exposure up-regulated free Fe2+ level and promoted lipid peroxidation and also up-regulated MARCHF1 (a novel E3 ligase of GPX4) level to promote the ubiquitination degradation of GPX4, both of which resulted in HUVEC ferroptosis. Furthermore, we also found that GPX4 protein down-regulated the protein levels of VEGFA and ANG-1, two key proteins function for angiogenesis, and thus suppressed HUVEC angiogenesis. In turn, supplement with GPX4 could suppress ferroptosis, recover angiogenesis, and alleviate miscarriage. Moreover, the levels of free Fe2+ and VEGFA in serum might predict the risk of miscarriage. Overall, this study uncovered the crosstalk among BaP/BPDE exposure, ferroptosis, angiogenesis, and miscarriage, discovering novel toxicological effects of BaP/BPDE on human reproductive health. This study also warned the public to avoid exposure to polycyclic aromatic hydrocarbons during pregnancy to effectively prevent adverse pregnancy outcomes.

Effects of Benzo[a]pyrene on Human Sperm Functions: An In Vitro Study

Benzo(a)pyrene (BaP) is considered one of the most dangerous air pollutants for adverse health effects, including reproductive toxicity. It is found both in male and female reproductive fluids likely affecting spermatozoa after the selection process through cervical mucus, a process mimicked in vitro with the swim-up procedure. In vitro effects of BaP (1, 5, 10 µM) were evaluated both in unselected and swim-up selected spermatozoa after 3 and 24 h of incubation. BaP reduced total, progressive and hyperactivated motility and migration in a viscous medium both in swim-up selected and unselected spermatozoa. Viability was not significantly affected in swim-up selected but was reduced in unselected spermatozoa. In swim-up selected spermatozoa, increases in the percentage of spontaneous acrosome reaction and DNA fragmentation were observed after 24 h of incubation, whereas no differences between the control and BaP-treated samples were observed in caspase-3 and -7 activity, indicating no effects on apoptotic pathways. ROS species, evaluated by staining with CellROX® Orange and Dihydroethidium, did not differ in viable spermatozoa after BaP treatment. Conversely, the percentage of unviable ROS-positive spermatozoa increased. Our study suggests that BaP present in male and female genital fluids may heavily affect reproductive functions of human spermatozoa.

BPDE exposure promotes trophoblast cell pyroptosis and induces miscarriage by up-regulating lnc-HZ14/ZBP1/NLRP3 axis

Environmental Benzo(a)pyrene (BaP) and its ultimate metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) are typical persistent organic pollutants and endocrine disrupting chemicals. BaP/BPDE exposure might cause human trophoblast cell dysfunctions and induce miscarriage. However, the underlying mechanisms remain largely elusive. In this study, we found that BPDE exposure induced human trophoblast cell pyroptosis by up-regulating NLRP3/Caspase1/GSDMD pathway. We also identified that lnc-HZ14 was highly expressed in BPDE-exposed trophoblast cells and in recurrent miscarriage (RM) vs healthy control (HC) villous tissues. Lnc-HZ14 promoted trophoblast cell pyroptosis by promoting IRF1-mediated ZBP1 transcription, increasing METTL3-mediated m6A methylation on NLRP3 mRNA and its stability, and also enhancing ZBP1/NLRP3 protein interactions. Knockdown of lnc-HZ14/ZBP1/NLRP3 axis could efficiently alleviate BPDE-induced trophoblast cell pyroptosis. Higher level of pyroptosis, as indicated by the up-regulation of lnc-HZ14/ZBP1/NLRP3 axis, was found in RM vs HC villous tissues. In BaP-exposed mouse model, BaP exposure induced placental tissue pyroptosis and miscarriage by up-regulating murine Zbp1/Nlrp3 axis, and knockdown of Nlrp3 could efficiently reduce placenta pyroptosis and alleviate BaP-induced mouse miscarriage. Serum IL-1β protein level might act as a promising indicator to predict the risk of miscarriage. These findings provided new insights into BaP/BPDE-induced trophoblast cell pyroptosis and miscarriage and might be helpful for further assessment of the toxicological effects of BaP/BPDE on the female reproduction.

Benzo[a]pyrene toxicokinetics in humans following dietary supplementation with 3,3'-diindolylmethane (DIM) or Brussels sprouts

Utilizing the atto-zeptomole sensitivity of UPLC-accelerator mass spectrometry (UPLC-AMS), we previously demonstrated significant first-pass metabolism following escalating (25-250 ng) oral micro-dosing in humans of [14C]-benzo[a]pyrene ([14C]-BaP). The present study examines the potential for supplementation with Brussels sprouts (BS) or 3,3'-diindolylmethane (DIM) to alter plasma levels of [14C]-BaP and metabolites over a 48-h period following micro-dosing with 50 ng (5.4 nCi) [14C]-BaP. Volunteers were dosed with [14C]-BaP following fourteen days on a cruciferous vegetable restricted diet, or the same diet supplemented for seven days with 50 g of BS or 300 mg of BR-DIM® prior to dosing. BS or DIM reduced total [14C] recovered from plasma by 56-67% relative to non-intervention. Dietary supplementation with DIM markedly increased Tmax and reduced Cmax for [14C]-BaP indicative of slower absorption. Both dietary treatments significantly reduced Cmax values of four downstream BaP metabolites, consistent with delaying BaP absorption. Dietary treatments also appeared to reduce the T1/2 and the plasma AUC(0,∞) for Unknown Metabolite C, indicating some effect in accelerating clearance of this metabolite. Toxicokinetic constants for other metabolites followed the pattern for [14C]-BaP (metabolite profiles remained relatively consistent) and non-compartmental analysis did not indicate other significant alterations. Significant amounts of metabolites in plasma were at the bay region of [14C]-BaP irrespective of treatment. Although the number of subjects and large interindividual variation are limitations of this study, it represents the first human trial showing dietary intervention altering toxicokinetics of a defined dose of a known human carcinogen.

Concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in Human Serum and Adipose Tissues and Stimulatory Effect of Naphthalene in Adipogenesis in 3T3-L1 Cells

Polycyclic aromatic hydrocarbons (PAHs) are one of the most prevalent classes of environmental pollutants. Some evidence shows that PAHs could be involved in human obesity. However, little is known about the distribution patterns of PAHs in human adipose tissue (AT) and the role of PAHs on adipogenesis/lipogenesis. The aims of this pilot study were to determine concentrations of 16 PAHs defined as high-priority pollutants in the plasma and adipose tissue of French and Polish bariatric patients, as well as their correlation with body mass index (BMI), plasma and AT adipokines expression levels. We finally investigated the role of naphthalene on cell proliferation, viability, and differentiation in 3T3-L1 preadipocytes. The concentration of most PAHs was similar in the three types of AT and it was significantly higher in AT as compared to plasma, suggesting bioaccumulation. Polish patients had higher PAH levels in AT than French ones. Only the concentration of naphthalene in AT was positively correlated with the BMI and serum or adipose chemerin, adiponectin and resistin expression, in French but not in Polish patients, who had significantly higher BMIs. Moreover, naphthalene exposure increased the cell proliferation of 3T3-L1 preadipocytes and lipogenesis, and increased the expression of genes involved in adipogenesis after cell differentiation. Taken together, PAHs and more particularly naphthalene could be an obesogenic molecule and increase the risk of obesity.

Molecularly tracing of children exposure pathways to environmental organic pollutants and the Autism Spectrum Disorder Risk

Organic pollutants (OPs) including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) have showed neuro-damaging effects, but studies concerning the autism spectrum disorder (ASD) risk are limited. A case-control study with ASD (n = 125) and healthy control (n = 125) children was conducted on the different land use settings across Punjab, Pakistan. Serum concentrations of 26 OCPs, 29 PCB congeners, 11 PBDEs and 32 PAHs were measured. Serum PCB77 (AOR = 2.00; 95% CI: 1.43, 2.18), PCB118 (AOR = 1.49; 95% CI: 1.00, 2.00), PCB128 (AOR = 1.65; 95% CI: 1.01, 1.91), PCB153 (AOR = 1.80; 95% CI: 1.55, 1.93) were significantly higher, but PCB187 (AOR = 0.37; 95% CI: 0.24, 0.49) was significantly lower in the ASD cases when compared to the controls. Serum BDE99 (AOR = 0.48; 95% CI: 0.26, 0.89) was significantly higher in the healthy controls than in the ASD cases. Among the analyzed OCPs, p,p'-DDE (AOR = 1.50; 95% CI: 1.00, 1.85) was significantly elevated in the ASD cases with comparison in the controls. For PAHs, serum dibenzothiophene (AOR = 7.30; 95% CI: 1.49, 35.85) was significantly higher in the ASD, while perylene (AOR = 0.25; 95% CI: 0.06, 1.10) and fluorene (AOR = 0.21; 95% CI: 0.06, 0.72) were significantly higher in the controls. In addition, many of the serum pollutants were significantly associated with GSTT1, GSTM1 (null/present polymorphism) and presented the genotypic variation to respond xenobiotics in children. The children living in proximity to urban and industrial areas had a greater exposure to most of the studied pollutants when compared to the rural children, however children residing in rural areas showed higher exposure to OCPs. This comprehensive study documents an association between environmental exposure risk of several organic pollutants (OPs) from some contaminated environmental settings with ASD risk in children from Pakistan.

Polycyclic Aromatic Hydrocarbons Induced by Smoking and Air Pollution: Correlation with Oxidative Stress in Chronic Obstructive Pulmonary Disease Patients

Oxidative stress is induced by tobacco smoking and is also associated with exposure to air pollution, which are two of the most important risk factors for chronic obstructive pulmonary disease (COPD). The aim of this study was to correlate tobacco use and exposure to air pollution with oxidative stress markers useful in clinical practice in patients with COPD. A total of 102 patients were included and the levels of polycyclic aromatic hydrocarbons (PAHs), malondialdehyde, uric acid and number of packs-years (PY) were determined. Also, six different ratios were used to assess the source of exposure. The results obtained in this study show an admission of pollutants according to smoking status (former smokers/smoker/non-smokers) quantified in average total concentrations for the group of patients with COPD of 4.12 ng/mL, 6.76 ng/mL, 6.04 ng/mL. The six ratios used show that in COPD, the content of PAHs in the blood could be a result of diesel emissions and fuel combustion. Uric acid levels were lower in the smoker group of COPD patients (mean = 5.21 mg/dL), which indicates that oxidative stress is intensified with each cigarette smoked. Additionally, high concentrations of malondialdehyde were quantified for smoking patients diagnosed with COPD (mean = 2.72 µmol/L) compared to former smokers (mean = 2.43 µmol/L) and non-smoking (mean = 2.32 µmol/L) patients, which is another indicator of the implication of smoking in oxidative stress in COPD patients.

Cigarette smoke is associated with up-regulation of inducible NOS and COX-2 protein expression and activity in granulosa cells of women undergoing in vitro fertilization

Cigarette smoke exposure represents a well-established ovotoxic exogenous stress, but the molecular mechanisms underlying of this effect are still unclear. Cigarette smoke upregulates inflammatory genes in the female reproductive organs, therefore an abnormal inflammation response may contribute to the impairment of female fertility. In this study we investigated for the first time the effect of cigarette smoke exposure on NOS and COX expression and activity and on their transcription factors (CREB and NF-kB) in human GCs and on the release of NO and PGE₂ in the FF in smoking and non-smoking patients undergoing IVF treatment. In addition, correlation analysis between AMH serum levels, an index of ovarian reserve, and smoking exposure or iNOS and COX-2 protein expression levels were performed using a Pearson correlation method. Cigarette smoke exposure resulted in a significant increase of iNOS and COX-2 protein expression together with an increase of iNOS activity and PGE₂ levels. pNF-kB and pCREB protein expression were upregulated in the GCs of smokers compared to non-smokers. The habit of smoking was negatively correlated with serum AMH levels, and positively correlated with iNOS and COX-2 protein expression levels. The data presented in the current study revealed a novel molecular mechanism underlying the toxic effects of cigarette smoke on fertility. Additional pathways mediating the effects of cigarette smoke exposure in human GCs cannot be excluded and should be investigated in future studies.

Indoor and outdoor air pollution and couple fecundability: a systematic review

BACKGROUND

Air pollution is both a sensory blight and a threat to human health. Inhaled environmental pollutants can be naturally occurring or human-made, and include traffic-related air pollution (TRAP), ozone, particulate matter (PM) and volatile organic compounds, among other substances, including those from secondhand smoking. Studies of air pollution on reproductive and endocrine systems have reported associations of TRAP, secondhand smoke (SHS), organic solvents and biomass fueled-cooking with adverse birth outcomes. While some evidence suggests that air pollution contributes to infertility, the extant literature is mixed, and varying effects of pollutants have been reported.

OBJECTIVE AND RATIONALE

Although some reviews have studied the association between common outdoor air pollutants and time to pregnancy (TTP), there are no comprehensive reviews that also include exposure to indoor inhaled pollutants, such as airborne occupational toxicants and SHS. The current systematic review summarizes the strength of evidence for associations of outdoor air pollution, SHS and indoor inhaled air pollution with couple fecundability and identifies gaps and limitations in the literature to inform policy decisions and future research.

SEARCH METHODS

We performed an electronic search of six databases for original research articles in English published since 1990 on TTP or fecundability and a number of chemicals in the context of air pollution, inhalation and aerosolization. Standardized forms for screening, data extraction and study quality were developed using DistillerSR software and completed in duplicate. We used the Newcastle-Ottawa Scale to assess risk of bias and devised additional quality metrics based on specific methodological features of both air pollution and fecundability studies.

OUTCOMES

The search returned 5200 articles, 4994 of which were excluded at the level of title and abstract screening. After full-text screening, 35 papers remained for data extraction and synthesis. An additional 3 papers were identified independently that fit criteria, and 5 papers involving multiple routes of exposure were removed, yielding 33 articles from 28 studies for analysis. There were 8 papers that examined outdoor air quality, while 6 papers examined SHS exposure and 19 papers examined indoor air quality. The results indicated an association between outdoor air pollution and reduced fecundability, including TRAP and specifically nitrogen oxides and PM with a diameter of ≤2.5 µm, as well as exposure to SHS and formaldehyde. However, exposure windows differed greatly between studies as did the method of exposure assessment. There was little evidence that exposure to volatile solvents is associated with reduced fecundability.

WIDER IMPLICATIONS

The evidence suggests that exposure to outdoor air pollutants, SHS and some occupational inhaled pollutants may reduce fecundability. Future studies of SHS should use indoor air monitors and biomarkers to improve exposure assessment. Air monitors that capture real-time exposure can provide valuable insight about the role of indoor air pollution and are helpful in assessing the short-term acute effects of pollutants on TTP.

The Damaging Effects of Long UVA (UVA1) Rays: A Major Challenge to Preserve Skin Health and Integrity

Within solar ultraviolet (UV) light, the longest UVA1 wavelengths, with significant and relatively constant levels all year round and large penetration properties, produce effects in all cutaneous layers. Their effects, mediated by numerous endogenous chromophores, primarily involve the generation of reactive oxygen species (ROS). The resulting oxidative stress is the major mode of action of UVA1, responsible for lipid peroxidation, protein carbonylation, DNA lesions and subsequent intracellular signaling cascades. These molecular changes lead to mutations, apoptosis, dermis remodeling, inflammatory reactions and abnormal immune responses. The altered biological functions contribute to clinical consequences such as hyperpigmentation, inflammation, photoimmunosuppression, sun allergies, photoaging and photocancers. Such harmful impacts have also been reported after the use of UVA1 phototherapy or tanning beds. Furthermore, other external aggressors, such as pollutants and visible light (Vis), were shown to induce independent, cumulative and synergistic effects with UVA1 rays. In this review, we synthetize the biological and clinical effects of UVA1 and the complementary effects of UVA1 with pollutants or Vis. The identified deleterious biological impact of UVA1 contributing to clinical consequences, combined with the predominance of UVA1 rays in solar UV radiation, constitute a solid rational for the need for a broad photoprotection, including UVA1 up to 400 nm.

In vitro testicular toxicity of environmentally relevant endocrine-disrupting chemicals: 2D vs. 3D models of prepubertal Leydig TM3 cells

The testis is a priority organ for developing alternative models to assess male reproductive health hazards of chemicals. This study characterized a 3D in vitro model of murine prepubertal Leydig TM3 cells with improved expression of steroidogenesis markers suitable for image-based screening of testicular toxicity. This 3D scaffold-free spheroid model was applied to explore the impact of prototypical endocrine-disrupting chemicals (EDCs) and environmental reprotoxicants (benzo[a]pyrene, 2- and 9-methylanthracenes, fluoranthene, triclosan, triclocarban, methoxychlor) on male reproductive health. The results were compared to the male reprotoxicity potential of EDCs assessed in a traditional monolayer (2D) culture. The testicular toxicity was dependent not only on the type of culture (2D vs. 3D models) but also on the duration of exposure. Benzo[a]pyrene and triclocarban were the most active compounds, eliciting cytotoxic effects in prepubertal Leydig cells at low micromolar concentrations, which might be a mechanism contributing to their male reprotoxicity.

Impact of benzo[a]pyrene with other pollutants induce the molecular alternation in the biological system: Existence, detection, and remediation methods

The exposure of benzo [a]pyrene (BaP) in recent times is rather unavoidable than ever before. BaP emissions are sourced majorly from anthropogenic rather than natural provenance from wildfires and volcanic eruptions. A major under-looked source is via the consumption of foods that are deep-fried, grilled, and charcoal smoked foods (meats in particular). BaP being a component of poly aromatic hydrocarbons has been classified as a Group I carcinogenic agent, which has been shown to cause both systemic and localized effects in animal models as well as in humans; has been known to cause various forms of cancer, accelerate neurological disorders, invoke DNA and cellular damage due to the generation of reactive oxygen species and involve in multi-generational phenotypic and genotypic defects. BaP's short and accumulated exposure has been shown in disrupting the fertility of gamete cells. In this review, we have discussed an in-depth and capacious run-through of the various origins of BaP, its economic distribution and its impact as well as toxicological effects on the environment and human health. It also deals with a mechanism as a single compound and its ability to synergize with other chemicals/materials, novel sensitive detection methods, and remediation approaches held in the environment.

Using Live Imaging and Fluorescence Ubiquitinated Cell Cycle Indicator Embryonic Stem Cells to Distinguish G1 Cell Cycle Delays for General Stressors like Perfluoro-Octanoic Acid and Hyperosmotic Sorbitol or G2 Cell Cycle Delay for Mutagenic Stressors like Benzo(a)pyrene

Lowest observable adverse effects level (LOAEL) is a standard point-of-departure dose in toxicology. However, first observable adverse effects level (FOAEL) was recently reported and is used, in this study, as one criterion to detect a mutagenic stimulus in a live imager. Fluorescence ubiquitinated cell cycle indicator (FUCCI) embryonic stem cells (ESC) are green in the S-G2-M phase of the cell cycle and not green in G1-phase. Standard media change here is a mild stress that delays G1-phase and media change increases green 2.5- to 5-fold. Since stress is mild, media change rapidly increases green cell number, but higher stresses of environmental toxicants and positive control hyperosmotic stress suppress increased green after media change. Perfluoro-octanoic acid (PFOA) and diethyl phthalate (DEP) previously suppressed progression of nongreen to green cell cycle progression. Here, bisphenol A (BPA), cortisol, and positive control hyperosmotic sorbitol also suppress green fluorescence, but benzo(a)pyrene (BaP) at high doses (10 μM) increases green fluorescence throughout the 74-h exposure. Since any stress can affect many cell cycle phases, messenger RNA (mRNA) markers are best interpreted in ratios as dose-dependent mutagens increase in G2/G1 and nonmutagens increase G1/G2. After 74-h exposure, RNAseq detects G1 and G2 markers and increasing BaP doses increase G2/G1 ratios but increasing hyperosmotic sorbitol and PFOA doses increase G1/G2 marker ratios. BaP causes rapid green increase in FOAEL at 2 h of stimulus, whereas retinoic acid caused significant green fluorescence increases only late in culture. Using a live imager to establish FOAEL and G2 delay with FUCCI ESC is a new method to allow commercial and basic developmental biologists to detect drugs and environmental stimuli that are mutagenic. Furthermore, it can be used to test compounds that prevent mutations. In longitudinal studies, uniquely provided by this viable reporter and live imager protocol, follow-up can be done to test whether the preventative compound itself causes harm.

A Novel Ex Vivo Approach Based on Proteomics and Biomarkers to Evaluate the Effects of Chrysene, MEHP, and PBDE-47 on Loggerhead Sea Turtles (Caretta caretta)

The principal aim of the present study was to develop and apply novel ex vivo tests as an alternative to cell cultures able to evaluate the possible effects of emerging and legacy contaminants in Caretta caretta. To this end, we performed ex vivo experiments on non-invasively collected whole-blood and skin-biopsy slices treated with chrysene, MEHP, or PBDE-47. Blood samples were tested by oxidative stress (TAS), immune system (respiratory burst, lysozyme, and complement system), and genotoxicity (ENA assay) biomarkers, and genotoxic and immune system effects were observed. Skin slices were analyzed by applying a 2D-PAGE/MS proteomic approach, and specific contaminant signatures were delineated on the skin proteomic profile. These reflect biochemical effects induced by each treatment and allowed to identify glutathione S-transferase P, peptidyl-prolyl cis-trans isomerase A, mimecan, and protein S100-A6 as potential biomarkers of the health-threatening impact the texted toxicants have on C. caretta. Obtained results confirm the suitability of the ex vivo system and indicate the potential risk the loggerhead sea turtle is undergoing in the natural environment. In conclusion, this work proved the relevance that the applied ex vivo models may have in testing the toxicity of other compounds and mixtures and in biomarker discovery.

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

•

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

•

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

•

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

•

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

•

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.

Indoor exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) to Canadian children: the Kingston allergy birth cohort

BACKGROUND

Canadian children are widely exposed to phthalates and polycyclic aromatic hydrocarbons (PAHs) from indoor sources. Both sets of compounds have been implicated in allergic symptoms in children.

OBJECTIVE

We characterize concentrations of eight phthalates and 12 PAHs in floor dust from the bedrooms of 79 children enrolled in the Kingston Allergy Birth Cohort (KABC).

METHOD

Floor dust was collected from the bedrooms of 79 children who underwent skin prick testing for common allergens after their first birthday. Data were collected on activities, household, and building characteristics via questionnaire.

RESULTS

Diisononyl phthalate (DiNP) and phenanthrene were the dominant phthalate and PAH with median concentrations of 561 µg/g and 341 ng/g, respectively. Benzyl butyl phthalate (BzBP) and chrysene had the highest variations among all tested homes, ranging from 1-95% to 1-99%, respectively.

SIGNIFICANCE

Some phthalates were significantly associated with product and material use such as diethyl phthalate (DEP) with fragranced products and DiNP and DiDP with vinyl materials. Some PAHs were significantly associated with household characteristics, such as benzo[a]pyrene with smoking, and phenanthrene and fluoranthene with the presence of an attached garage. Socioeconomic status (SES) had positive and negative relationships with some concentrations and some explanatory factors. No significant increases in risk of atopy (positive skin prick test) was found as a function of phthalate or PAH dust concentrations.

Long-term in vitro exposure of human granulosa cells to the mixture of endocrine disrupting chemicals found in human follicular fluid disrupts steroidogenesis

Most in vitro studies examine the effects of a single ED or a mixture of EDs on granulosa cells using short-term exposure; however, this approach is unlikely to reflect long-term, real-life exposures that are common in humans. We established an in vitro model that mimics long-term exposure of granulosa cells to real-life ED mixture. Human granulosa cells, HGrC1, were exposed to the mixture consisting of bisphenol A, polychlorinated biphenyl 153, benzo[a]pyrene, and perfluorooctanesulfonate in concentrations found in human follicular fluid (MIX) for 48 h and 4 weeks. Only long-term exposure to MIX decreased estradiol production after 2 and 3 weeks, and CYP19A1 protein after 2 weeks of exposure. By week 4, the cells restored estradiol production and CYP19A1 protein level. MIX increased basal progesterone production after 3 and 4 weeks of exposure but did not affect STAR and CYP11A1 mRNA. Cells that had been exposed to MIX for 4 weeks showed augmentation of forskolin-stimulated progesterone production. These results demonstrate that only long-term exposure to MIX alters steroidogenesis in HGrC1. This study also revealed that adverse effects of MIX on steroidogenesis in HGrC1 occurred a few weeks into MIX exposure and that this effect can be transient.

Characterization of the ERK1/2 phosphorylation profile in human and fish liver cells upon exposure to chemicals of environmental concern

We developed phospho-ERK1/2 ELISA for human and rainbow trout liver cells, employing HepG2 and RTL-W1 cell lines as models. The assay was applied to detect changes in ERK1/2 activity for nine chemicals, added over a wide concentration range and time points. Cell viability was measured to separate ERK1/2 regulation from cytotoxicity. Perfluorooctane sulfonate and carbendazim did not change ERK1/2 activity; influence on ERK1/2 due to cytotoxicity was indicated for tributyltin and cypermethrin. Mancozeb, benzo[a]pyrene, and bisphenol A stimulated ERK1/2 up to ∼2- (HepG2) and 1.5 (RTL-W1)-fold, though the kinetics differed between chemicals and cell lines. Bisphenol A and benzo[a]pyrene were the most potent concentration-wise, altering ERK1/2 activity in pM (HepG2) to nM (RTL-W1) range. While atrazine and ibuprofen increased ERK1/2 activity by ∼2-fold in HepG2, they did not initiate an appreciable response in RTL-W1. This assay proved to be a sensitive, medium- to high-throughput tool for detecting unrecognized ERK1/2-disrupting chemicals.

Mogroside V Alleviates Oocyte Meiotic Defects and Quality Deterioration in Benzo(a)pyrene-Exposed Mice

Accumulating evidence has demonstrated that benzo(a)pyrene (BaP) exposure adversely affects female reproduction, especially oocyte meiotic maturation and subsequent embryo development. Although we previously found that mogroside V (MV), a major bioactive component of S. grosvenorii, can protect oocytes from quality deterioration caused by certain stresses, whether MV can alleviate BaP exposure-mediated oocyte meiotic defects remains unknown. In this study, female mice were exposed to BaP and treated concomitantly with MV by gavage. We found that BaP exposure reduced the oocyte maturation rate and blastocyst formation rate, which was associated with increased abnormalities in spindle formation and chromosome alignment, reduced acetylated tubulin levels, damaged actin polymerization and reduced Juno levels, indicating that BaP exposure results in oocyte nucleic and cytoplasmic damage. Interestingly, MV treatment significantly alleviated all the BaP exposure-mediated defects mentioned above, indicating that MV can protect oocytes from BaP exposure-mediated nucleic and cytoplasmic damage. Additionally, BaP exposure increased intracellular ROS levels, meanwhile induced DNA damage and early apoptosis in oocytes, but MV treatment ameliorated these defective parameters, therefore it is possible that MV restored BaP-mediated oocyte defects by reducing oxidative stress. In summary, our findings demonstrate that MV might alleviate oocyte meiotic defects and quality deterioration in BaP-exposed mice.

Effect of prenatal exposure to Benzo[a]pyrene on ovarian toxicity and reproductive dysfunction: Protective effect of atorvastatin in the embryonic period

As an environmental contaminant, Benzo[a]pyrene (B[a]P; BaP) disrupts the antioxidant signaling and thus leads to the induction of oxidative stress and the damage of DNA in the ovary. low-dose atorvastatin (ATV) has antioxidant and anti-apoptotic properties. The present study aimed to survey the effects of prenatal exposure to BaP on ovarian toxicity and also to investigate the protective role of ATV in reducing ovarian toxicity. In this study, rats were divided into seven groups: control, ATV (10 mg/kg), oil, BaP (10 and 20 mg/kg), and ATV + BaP (10 and 20 mg/kg). BaP and ATV were administrated from gestation day 7-16 (GD7 to GD16), orally. 10 weeks after the birth, female offsprings were examined for oxidative stress markers, sex hormones, ovarian and tubular tissue structure, and the apoptosis markers. Data showed that BaP significantly reduced glutathione, increased malondialdehyde level, and disrupted the tissue structure of the ovary. Moreover, estrogen and progesterone levels significantly decreased in the offsprings rats. Also, BaP increased caspase-3 immunoreactivity. Atorvastatin treatment along with BaP in the embryonic period were able to bring the antioxidant status and sex hormones levels relatively close to normal. Besides, histological findings showed that atorvastatin was able to improve ovarian and oviduct abnormalities caused by BaP. Based on the above studies be concluded that atorvastatin in the embryonic during was able to reduce ovarian damage caused by BaP with antioxidant and anti-apoptotic properties.

Polycyclic aromatic hydrocarbons residues and the carcinogenic risk assessment to pregnant women in Nantong, China using QuEChERS method and HPLC-A pilot case study

A high-performance liquid chromatographic method with a modified QuEChERS extraction for the determination of polycyclic aromatic hydrocarbons (PAHs) in blood serum was developed to investigate the internal exposure level and the carcinogentic toxicity contribution rate of PAHs for pregnant women in Nantong, China. Venous blood (n = 48) was collected in the local hospital and the internal exposure level of 16 PAHs and the contribution rate of carcinogenicity to pregnant women were analyzed. Among all of the detected PAHs, the detection rate of pyrene (77.08%) was the highest, followed by naphthalene (64.58%) and benzo[a]anthracene (BaA, 45.83%). The carcinogenicity contribution rate of BaA (37.37%) was the highest, followed by fluorene (32.96%) and acenaphthylene (22.01%). The results showed that many kinds of carcinogenic PAHs can be detected in the serum of pregnant women in Nantong city, among which BaA should be paid most attention because of its high internal exposure level and carcinogenic risk. Meanwhile, the origins of general PAHs in serum samples were analyzed using the characteristic ratio analysis method. The PAH pollution level of air samples (n = 42) during the collection time of blood samples was also analyzed to compare the possible correlations between the two different results.

Co-exposure of Bi2O3 nanoparticles and bezo[a]pyrene-enhanced in vitro cytotoxicity of mouse spermatogonia cells

Recent attention has been focused on reproductive toxicity of nanoscale materials in combination with pre-existing environmental pollutants. Due to its unique characteristics, bismuth (III) oxide (Bi₂O₃) nanoparticles (BONPs) are being used in diverse fields including cosmetics and biomedicine. Benzo[a]pyrene (BaP) is a known endocrine disruptor that most common sources of BaP exposure to humans are cigarette smoke and well-cooked barbecued meat. Hence, joint exposure of BONPs and BaP in humans is common. There is scarcity of information on toxicity of BONPs in combination with BaP in human reproductive system. In this work, combined effects of BONPs and BaP in mouse spermatogonia (GC-1 spg) cells were assessed. Results showed that combined exposure of BONPs and BaP synergistically induced cell viability reduction, lactate dehydrogenase leakage, induction of caspases (-3 and -9) and mitochondrial membrane potential loss in GC-1 spg cells. Co-exposure of BONPs and BaP also synergistically induced production of pro-oxidants (reactive oxygen species and hydrogen peroxide) and reduction of antioxidants (glutathione and several antioxidant enzymes). Experiments with N-acetyl-cysteine (NAC, a reactive oxygen species scavenger) indicated that oxidative stress was a plausible mechanism of synergistic toxicity of BONPs and BaP in GC-1 spg cells. Present data could be helpful for future in vivo research and risk assessment of human reproductive system co-exposed to BONPs and BaP.

Vitamin C prevents epidermal damage induced by PM-associated pollutants and UVA1 combined exposure

Particulate matter is suspected to be substantially involved in pollution-induced health concerns. In fact, ultrafine particles (UFPs) contain polycyclic aromatic hydrocarbons (PAHs) known as mutagenic, cytotoxic and sometimes phototoxic. Since UFPs reach blood circulation from lung alveoli, deep skin is very likely contaminated by PAHs coming from either skin surface or blood. As photoreactive, benzo(a)pyrene (BaP) or indenopyrene (IcdP) is involved in the interplay between pollution and sunlight. In order to better characterize this process, experiments were carried out on reconstructed human epidermis (RHE) in a protocol mimicking realistic exposure. Concentrations of PAHs comparable to those generally reported in blood were used together with chronic irradiation to low dose UVA1. On a histological level, damaged cells mainly accumulated in a suprabasal situation, thus reducing living epidermis thickness. Stress markers such as IL1-α or MMP3 secretion increased, and surprisingly, the histological position of Transglutaminase-1 within epidermis was disturbed, whereas position of other differentiation markers (keratin-10, filaggrin, loricrin) remained unchanged. When vitamin C was added in culture medium, a very significant protection involving all markers was noticed. In conclusion, we provide here a model of interest to understand the epidermal deleterious consequences of pollution and to select efficient protective compounds.

Effects of Cigarette Smoking on Preimplantation Embryo Development

In this chapter, we first gave a brief introduction to the detriments of cigarette smoking, with an emphasis on its adverse effects on female reproductive health. Then, we outlined recent advances about the impacts of cigarette smoke on preimplantation embryo development. Additionally, toxicities of cadmium and benzo(a)pyrene (BaP) at this specific developmental window were also discussed, to illustrate the potential mechanisms involved in cigarette smoke-associated embryotoxicity. Finally, we provide an overview of the issues to be solved in the future research. Further studies about the molecular mechanism of cigarette smoking-associated female infertility may provide vital insights into developing new interventions for the women smokers and thus improving their reproductive outcomes.

Toxicological Effects of BPDE on Dysfunctions of Female Trophoblast Cells

Polycyclic aromatic hydrocarbons (PAHs) are widely spread persistent environmental toxicants. Its typical representative benzo[a]pyrene (BaP) is a human carcinogen. BaP can pass through the placental barrier and is finally metabolized into benzo[a]pyren-7, 8-dihydrodiol-9, 10-epoxide (BPDE). BPDE can form DNA adducts, which directly affect the female reproductive health. Based on the special physiological functions of trophoblast cells and its important effect on normal pregnancy, this chapter describes the toxicity and molecular mechanism of BPDE-induced dysfunctions of trophoblast cells. By affecting the invasion, migration, apoptosis, proliferation, inflammation, and hormone secretion of trophoblast cells, BPDE causes diseases such as choriocarcinoma, intrauterine growth restriction, eclampsia, and abortion. In the end, it is expected to provide a scientific basis and prevention approach for women's reproductive health and decision-making basis for the formulation of environmental health standards.

Endocrine-Disrupting Air Pollutants and Their Effects on the Hypothalamus-Pituitary-Gonadal Axis

Anthropogenic endocrine-disrupting chemicals (EDCs) can contaminate air, soil, and water. Human exposures to EDCs occur through inhalation, absorption, and ingestion. EDCs act by disrupting various pathways in the endocrine system. When the hypothalamic–pituitary–gonadal (HPG) axis is disrupted by EDCs, there can be effects on fertility in both men and women. Not only can fertility be indirectly affected by EDC disruptions of the HPG axis, but EDCs can also directly affect the menstrual cycle and sperm morphology. In this review, we will discuss the current findings on EDCs that can be inhaled. This review examines effects of exposure to prominent EDCs: brominated and organophosphate flame retardants, diesel exhaust, polycyclic aromatic hydrocarbons, cadmium and lead, TCDD, and polychlorinated biphenyls on fertility through alterations that disrupt the HPG axis and fertility through inhalation. Although the studies included herein include multiple exposure routes, all the studies indicate receptor interactions that can occur from inhalation and the associated effects of all compounds on the HPG axis and subsequent fertility.

Environmental Pollutant Benzo[a]pyrene Induces Recurrent Pregnancy Loss through Promoting Apoptosis and Suppressing Migration of Extravillous Trophoblast

Methods

The implantation sites, fetus resorption, and abnormal fetuses were studied in pregnant mice treated with different doses of BaP by oral gavage from day 1 to day 10 of gestation. Additionally, apoptosis and related signaling pathway, and the migration and invasion of trophoblasts, were assessed before and after exposure of BPDE in Swan 71 trophoblast cell. Besides, the migration and invasion, and its related signaling pathway, were assessed in villi obtained from women.

Results

We observed a concentration-dependent incidence of abnormal murine fetuses, beginning with 0.1 mg/kg BaP; with a BaP concentration of 2 mg/kg, no fetuses developed. Correspondingly, a BPDE concentration-dependent apoptosis of human trophoblasts. Beginning with 0.5 μM BPDE exposure, Bax/Caspase-3 were increased and Bcl-2 decreased. Furthermore, BPDE also inhibited, in a dose-dependent manner, the migration of villous explants from elective abortion women, consistent with the reduced migration of villous explants from women with recurrent pregnancy loss (RPL), and reduced the cell immigration in Swan 71 trophoblasts, in a dose-dependent manner measured by transwell assays.

Conclusions

Our study results provide mechanistic insight to the effect of BPDE on trophoblast dysfunction through enhanced cell apoptosis and inhibited migration, providing further experimental evidence to the causative links between BaP exposure and PRL.

Looking Inside the World of Granulosa Cells: The Noxious Effects of Cigarette Smoke

The detrimental implications of tobacco smoke on systemic health have been widely established during the past few decades. Nonetheless, increasing evidence has begun to shed more light on the serious impact that smoke exposure could also have on mammal reproductive health in terms of overall ovarian dysfunction and gestation. A variety of these complications seem to be causally related to specific chemical substances contained in cigarette smoke and their possible effects on ovarian tissues and cells, such as granulosa cells. Granulosa cells represent the functional unit of the ovary and are able to establish a bidirectional cross-talk relationship with the oocyte during folliculogenesis, which makes them vital for its correct growth and development. Based on these premises, the current review focuses on the presence of related smoke-induced damages in granulosa cells. Data have been grouped according to the studied tobacco constituents and the molecular pathways involved, in order to synthesize their impact on granulosa cells and fertility. Attention is further brought to the correlation between electronic cigarettes and female reproduction, although there have been no investigations so far regarding e-cigarette-related granulosa cell exposure. We summarize how tobacco constituents are able to cause alterations in the "life" of granulosa cells, ranging from luteal steroidogenesis and follicular loss to granulosa cell apoptosis and activation of the autophagic machinery. Further studies have been conducted to elucidate the relationship between lifestyle and fertility as to reduce the morbidity connected with infertility.

The protective role of ginsenoside compound K in porcine oocyte meiotic maturation failed caused by benzo(a)pyrene during in vitro maturation

Benzo(a)pyrene (BaP) is a pollutant and carcinogen derived from air pollution. It causes serious damage to reproductive system, especially ovary. Ginseng is always used in food and traditional medicine as a nutraceuticals or herbal medicine. Ginsenoside compound K (CK) is a major bioactive ingredient of ginseng, that shows very specific anti-apoptosis, anti-oxidant, and anti-inflammatory activities and thus, it protects cells from damage. The aim of this study was to investigate the effects of CK on the BaP-induced inhibition of the in vitro maturation of porcine oocytes and their subsequent embryonic development capacity. We found that supplementation with 10 μg mL^-1 CK during in vitro maturation significantly increased maturation rate (P < 0.05) and the expression level of related genes after damage induced by 40 μM BaP treatment. In addition, reactive oxygen species (ROS) levels significantly decreased and ATP content and mitochondrial membrane potential (MMP) increased after CK supplementation (P < 0.05). The competence for embryonic development was improved by the induction of pluripotency gene expression and the inhibition of apoptosis after CK supplementation of BaP-treated oocytes. Supplementation with 10 μg mL^-1 CK improved porcine oocyte maturation and subsequent embryonic development of parthenogenetic activation (33.01 vs. 20.92, P < 0.05) and in vitro fertilization (24.01 vs. 16.52, P < 0.05) by increasing antioxidant activity and improving mitochondrial function after BaP-induced damage.

Association of exposure to secondhand smoke at home with early age at menarche in South Korea

OBJECTIVES

The secular trend in age at menarche (AAM) has declined both worldwide and in Korea. Early AAM is associated with the risk of several diseases, reproductive capacity, and psychological problems. We aimed to investigate the relationship between secondhand smoke (SHS) exposure at home and early puberty onset using AAM in Korean adolescents.

STUDY DESIGN

This is a retrospective cross-sectional study.

METHODS

This study used data from the Korea Youth Risk Behavior Web-based Survey 2014-2015. We used the mean AAM (12.2 years) as a determinant of early AAM. After the exclusion of girls without menarche or who did not respond, the total population comprised 63,618 participants. We categorized AAM as 'early' and 'average or late.' Adolescents with SHS exposure were assigned to the 'never exposed,' 'light exposure,' and 'heavy exposure' groups. Multiple logistic regression analyses were performed.

RESULTS

We observed a positive association, approximately 1.12 times, between early AAM and high SHS exposure (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.05-1.19). Girls who started smoking before the age of 12 years (OR, 1.68; 95% CI, 1.41-1.99) showed a stronger association with early AAM than non-smokers. Active smoking showed a stronger association with early AAM. Never smokers with high SHS exposure at home were 1.13 times likelier to have an early AAM (OR, 1.13; 95% CI, 1.05-1.22) than those without SHS exposure.

CONCLUSIONS

In addition to active smoking, SHS may also be a risk factor for early AAM. Education aimed at active and secondhand smoking prevention is needed to protect children against early AAM.

Exposure to polycyclic aromatic hydrocarbons and risk for premature ovarian failure and reproductive hormones imbalance

Polycyclic aromatic hydrocarbons (PAHs) are a typical class of persistent organic pollutants that is ubiquitous worldwide. Previous animal studies suggested that PAHs had adverse effects on female reproduction. However, the human data regarding relationship of PAHs exposure with women reproductive health, such as ovarian dysfunction, are scarce. In this case-control study, the associations of serum levels of PAHs with the risk of premature ovarian failure (POF) and reproductive hormones in Chinese women were investigated, with recruiting 157 POF patients and 217 healthy women. The serum levels of 12 types of PAHs, as well as reproductive hormones, including follicle-stimulating hormone, luteinizing hormone and anti-mullerian hormone, were determined. In the logistic regression models, most individual PAH congeners showed significantly positive correlations with the risk of POF (p < 0.05), except for fluorine and pyrene. Benzo(a)pyrene (BaP), as the most carcinogenic PAH congener, was observed to be significantly positively associated with the risk of POF. After adjustment for age, body mass index, educational levels and household income, per one-unit increase in the log-transformed BaP concentration was significantly correlated with 2.191-fold increased risk of POF (OR = 2.191, 95%CI: 1.634-2.938, p < 0.05). To the best of our knowledge, this is the first study to report an association between internal exposure levels of PAHs and the increased risk of POF in women.

Does cigarette smoking really have a clinical effect on folliculogenesis and oocyte maturation?

Infertility is the most common issue in the field of reproductive medicine. Many factors affect fertility status, including life-style choices such as cigarette smoking or alcohol use. The aim of this study was to investigate the effects of cigarette smoking on oocyte quality as well the quantity in young fertile women. In total, 56 young fertile women who were undergoing oocyte donation programmes were included in this study. The effects of cigarette smoking on antral follicle count, number of follicles and oocytes retrieved and morphology were assessed by an expert embryologist. The results of this study showed that cigarette smoking did not have a significant effect on the follicle count or the number of oocytes retrieved from young and fertile women. However, a significant difference was observed in the morphological assessment. In conclusion, although cigarette smoking does not seem to affect oocyte development, it had an effect on cytoplasmic anomalies and therefore may lower pregnancy chance. Therefore, it is crucial to give proper counselling to patients who are trying to become pregnant both naturally and by in vitro fertilization.

In Vitro Methods to Simulate Pollution and Photo-Pollution Exposure in Human Skin Epidermis

Tissue homeostasis of an individual is a finely orchestrated phenomenon that ensures integrity and steady state in health. Emerging evidence indicates that the environment, especially ambient air pollution, has a lasting impact on this equilibrium (Beelen et al., Lancet 383:785-795, 2014). Environmental pollution consists of diverse entities, namely, particulate matter (PM 2.5, PM 10), ozone, and UV rays, among others (Heroux et al., Int J Public Health 60:619-627, 2015). Understandably, skin epidermis is the first and the most exposed tissue to such a wide range of substances and bears the assault. Previous studies have established that exposure to atmospheric pollution aggravates several skin disorders as, for instance, eczema, acne, lentigines or macules, and wrinkles (Araviiskaia et al., J Eur Acad Dermatol Venereol 33:1496-1505, 2019). While pollutants can interact with skin surface, contamination of deep skin by particulate matter (either ultrafine particles or by some polycyclic aromatic hydrocarbon (PAH) moieties) is also highly probable, particularly because PAH were detected in blood and inside the cortex of hair (Guo et al., Sci Total Environ 427-428:35-40, 2012; Palazzi et al., Environ Int 121:1341-1354, 2018). Importantly, concentrations of contaminant PAH in the blood are very low, in the nanomolar range (Neal et al., Reprod Toxicol 25:100-106, 2008); thus PAH levels in the skin might be in a similar range. Furthermore, it has been shown that some PAH (e.g., benzo[a]pyrene, indenopyrene) are phototoxic under UVA irradiation through a strong production of reactive oxygen species, ultimately leading to skin cancer in mice (Burke and Wei, Toxicol Ind Health 25:219-224, 2009). Since UVA1 (340-400 nm) can reach deep dermis, it can thus be assumed that photoactivation of PAH contaminants in living skin may locally induce a significant stress. In order to study the molecular mechanisms that are affected due to this exposure, there is an increasing need to develop reliable and diverse methods that simulate pollution exposure.

Maternal benzo[a]pyrene exposure is correlated with the meiotic arrest and quality deterioration of offspring oocytes in mice

Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) in particulate matter that has a diameter of ≤2.5 μm (PM2.5). Studies have demonstrated that BaP exposure causes oocyte meiotic arrest in mice. However, whether BaP exposure also affects oocyte maturation in offspring remains unclear. To test this, female mice were administered BaP before pregnancy to generate BaP-exposed offspring. Our findings showed that BaP exposure reduced the in vitro maturation and increased the abnormalities of meiotic apparatus in offspring oocytes. In addition, BaP exposure reduced the mitochondrial content and intracellular ATP generation, induced early apoptosis, increased reactive oxidative species accumulation and the genomic DNA 5-methylcytosine (5mc) level in offspring oocytes. Along with the abovementioned defective parameters, maternal BaP exposure further compromised the embryo developmental competence of offspring oocytes. In summary, our study demonstrated that maternal BaP exposure compromised offspring oocyte maturation and quality.

In Utero Exposure to Benzo[a]pyrene Induces Ovarian Mutations at Doses That Deplete Ovarian Follicles in Mice

Polycyclic aromatic hydrocarbons like benzo[a]pyrene (BaP) are ubiquitous environmental contaminants formed during incomplete combustion of organic materials. Our prior work showed that transplacental exposure to BaP depletes ovarian follicles and increases prevalence of epithelial ovarian tumors later in life. We used the MutaMouse transgenic rodent model to address the hypothesis that ovarian mutations play a role in tumorigenesis caused by prenatal exposure to BaP. Pregnant MutaMouse females were treated with 0, 10, 20, or 40 mg/(kg day) BaP orally on gestational days 7-16, covering critical windows of ovarian development. Female offspring were euthanized at 10 weeks of age; some ovaries with oviducts were processed for follicle counting; other ovaries/oviducts and bone marrow were processed for determination of lacZ mutant frequency (MF). Mutant plaques were pooled within dose groups and sequenced to determine the mutation spectrum. BaP exposure caused highly significant dose-related decreases in ovarian follicles and increases in ovarian/oviductal and bone marrow mutant frequencies at all doses. Absence of follicles, cell packets, and epithelial tubular structures were observed with 20 and 40 mg/(kg day) BaP. Depletion of ovarian germ cells was inversely associated with ovarian MF. BaP induced primarily G > T and G > C transversions and deletions in ovaries/oviducts and bone marrow cells and produced a mutation signature highly consistent with that of tobacco smoking in human cancers. Overall, our results show that prenatal BaP exposure significantly depletes ovarian germ cells, causes histopathological abnormalities, and increases the burden of ovarian/oviductal mutations, which may be involved in pathogenesis of epithelial ovarian tumors. Environ. Mol. Mutagen. 60:410-420, 2019. © 2018 Her Majesty the Queen in Right of Canada.