Oxidative stress-induced DNA damage by particulate air pollution

The associations of air pollution exposure during pregnancy with fetal growth and anthropometric measurements at birth: a systematic review and meta-analysis

Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air pollution during pregnancy on fetal growth have been investigated using ultrasound in many previous studies, the results were inconsistent and disputable. We aimed to qualitatively and quantitatively investigate the associations of air pollution exposure during different periods of pregnancy with fetal growth and anthropometric measurements at birth. We searched for all studies investigating the associations of air pollution exposure during pregnancy with fetal growth and birth anthropometric measurements in English and Chinese databases published before July 31, 2017. A random-effects model was employed in the meta-analysis to estimate the pooled effects of each 10 μg/m³ increment in air pollutant exposure. The ACROBAT-NRSI tool was applied to assess the quality of each included study, and the GRADE tool was employed to assess the overall quality of the meta-analysis. Maternal PM_2.5 exposure (10 μg/m³) during the entire pregnancy was negatively associated with head circumference at birth (β = - 0.30 cm, 95% CI - 0.49, - 0.10), and NO₂ exposure during the entire pregnancy was significantly linked to shorter length at birth (β = - 0.03 cm, 95% CI - 0.05, - 0.02). Maternal exposure to higher NO₂ and PM_2.5 during pregnancy may impair neonatal head circumference and length development, respectively. More studies are needed to confirm the effects of NO₂ and PM_2.5 and to identify the sources and major toxic components of PMs.

Time-Varying Exposure to Air Pollution and Outcomes of in Vitro Fertilization among Couples from a Fertility Clinic

BACKGROUND

A few studies suggest that air pollution may decrease fertility, but prospective studies and examinations of windows of susceptibility remain unclear.

OBJECTIVE

We aimed to examine the association between time-varying exposure to nitrogen dioxide ([Formula: see text]), ozone ([Formula: see text]), fine particulate matter [Formula: see text] ([Formula: see text]), and black carbon (BC) on in vitro fertilization (IVF) outcomes.

METHODS

We included 345 women (522 IVF cycles) for the [Formula: see text], [Formula: see text], and [Formula: see text] analyses and 339 women (512 IVF cycles) for the BC analysis enrolled in a prospective cohort at a Boston fertility center (2004–2015). We used validated spatiotemporal models to estimate daily residential exposure to [Formula: see text], [Formula: see text], [Formula: see text], and BC. Multivariable discrete time Cox proportional hazards models with four periods [ovarian stimulation (OS), oocyte retrieval to embryo transfer (ET), ET to implantation, implantation to live birth] estimated odds ratios (OR) and 95% confidence intervals (CI) of failing at IVF. Time-dependent interactions were used to identify vulnerable periods.

RESULTS

An interquartile range (IQR) increase in [Formula: see text], [Formula: see text], and BC throughout the IVF cycle was associated with an elevated odds of failing at IVF prior to live birth ([Formula: see text], 95% CI: 0.95, 1.23 for [Formula: see text]; [Formula: see text], 95% CI: 0.88, 1.28 for [Formula: see text]; and [Formula: see text], 95% CI: 0.96, 1.41 for BC). This relationship significantly varied across the IVF cycle such that the association with higher exposure to air pollution during OS was strongest for early IVF failures. An IQR increase in [Formula: see text], [Formula: see text], and BC exposure during OS was associated with 1.42 (95% CI: 1.20, 1.69), 1.26 (95% CI: 0.96, 1.67), and 1.23 (95% CI: 0.96, 1.59) times the odds of failing prior to oocyte retrieval, and 1.32 (95% CI: 1.13, 1.54), 1.27 (95% CI: 0.98, 1.65), and 1.32 (95% CI: 1.10, 1.59) times the odds of failing prior to ET.

CONCLUSION

Increased exposure to traffic-related pollutants was associated with higher odds of early IVF failure. https://doi.org/10.1289/EHP4601.

Maternal Residential Proximity to Major Roadways and the Risk of Childhood Acute Leukemia: A Population-Based Case-Control Study in Texas, 1995-2011

Acute leukemia is the most common pediatric malignancy. Some studies suggest early-life exposures to air pollution increase risk of childhood leukemia. Therefore, we explored the association between maternal residential proximity to major roadways and risk of acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). Information on cases with acute leukemia (n = 2030) was obtained for the period 1995-2011 from the Texas Cancer Registry. Birth certificate controls were frequency matched (10:1) on birth year (n = 20,300). Three residential proximity measures were assessed: (1) distance to nearest major roadway, (2) residence within 500 meters of a major roadway, and (3) roadway density. Multivariate logistic regression was used to generate adjusted odds ratios (aOR) and 95% confidence intervals (CI). Mothers who lived ≤500 meters to a major roadway were not more likely to have a child who developed ALL (OR = 1.03; 95% CI: 0.91-1.16) or AML (OR = 0.84; 95% CI: 0.64-1.11). Mothers who lived in areas characterized by high roadway density were not more likely to have children who developed ALL (OR = 1.06, 95% CI: 0.93-1.20) or AML (OR = 0.83, 95% CI: 0.61-1.13). Our results do not support the hypothesis that maternal proximity to major roadways is strongly associated with childhood acute leukemia. Future assessments evaluating the role of early-life exposure to environmental factors on acute leukemia risk should explore novel methods for directly measuring exposures during relevant periods of development.

Genotoxic effects of PM10 and PM2.5 bound metals: metal bioaccessibility, free radical generation, and role of iron

The present study was undertaken to examine the possible genotoxicity of ambient particulate matter (PM₁₀ and PM_2.5) in Pune city. In both size fractions of PM, Fe was found to be the dominant metal by concentration, contributing 22% and 30% to the total mass of metals in PM₁₀ and PM_2.5, respectively. The speciation of soluble Fe in PM₁₀ and PM_2.5 was investigated. The average fraction of Fe³⁺ and Fe²⁺ concentrations in PM_2.5 was 80.6% and 19.3%, respectively, while in PM_2.5 this fraction was 71.1% and 29.9%, respectively. The dominance of Fe(III) state in both PM fractions facilitates the generation of hydroxyl radicals (^·OH), which can damage deoxyribose nucleic acid (DNA), as was evident from the gel electrophoresis study. The DNA damage by ^·OH was supported through the in silico density functional theory (DFT) method. DFT results showed that C8 site of guanine (G)/adenine (A) and C6 site of thymine (T)/cytosine (C) would be energetically more favorable for the attack of hydroxyl radicals, when compared with the C4 and C5 sites. The non-standard Watson-Crick base pairing models of oxidative products of G, A, T and C yield lower-energy conformations than canonical dA:dT and dG:dC base pairing. This study may pave the way to understand the structural consequences of base-mediated oxidative lesions in DNA and its role in human diseases.

The global DNA and RNA methylation and their reversal in lung under different concentration exposure of ambient air particulate matter in mice

Particulate matter (PM) in air pollution is a pervasive risk factor in pulmonary diseases that are always associated with gene expression level alterations in many specific-genes. DNA methylation (5-methylcytosine [5mC]) and RNA methylation (N6-methyladenine [6 mA]) influence the gene expression from transcription and post-transcription level, and the DNA hydroxymethylation (5-hydroxymethylcytosine [5hmC]) is the oxidized form of 5mC. In the present study, the levels of global 5mC, 5hmC and 6 mA of lungs in experimental mice were investigated. We divided the animals into 3 groups randomly, the group 1 was exposed to heavy PM for 24 h in the unfiltered chamber, the group 2 was exposed to filtered air in the filtered chamber, and the group 3 was 10 of the mice in the group 1 after 24 h exposure and then being moved to the filtered chamber for further 120 h exposure. The morphology of lungs showed that acute PM exposure impaired the structure of pulmonary alveolus. Meanwhile, the global level of DNA methylation was decreased, and DNA hydroxymethylation and RNA methylation levels were increased in lungs after PM exposure for only 24 h. Very notably, after being exposed in purified air for 120 h, the pulmonary morphology, the global levels of DNA methylation, DNA hydroxymethylation and RNA methylation of lungs were all reversed. The present study clearly demonstrated the alteration of DNA and RNA methylation after acute heavy PM exposure and emphasized the reversal of the symptoms caused by PM exposure after the air purification, which provided us a new idea for the intervention of the adverse health effects from air pollution. CAPSULE: Acute PM exposure resulted in reduced global DNA methylation and increased global DNA hydroxymethylcytosine and RNA methylation, and air purification reversed these alterations.

Biochemical evidence on the potential role of methyl mercury in hepatic glucose metabolism through inflammatory signaling and free radical pathways

Methylmercury (MeHg) is an extremely important environmental toxicant posing serious health risks to human health and a big source of environmental pollutant. Numerous evidence available showing a link between nervous system toxicity and MeHg exposure. Other forms of mercury are reason of metabolic toxic effects and alteration of DNA in the human body. The sources of exposure could be occupational or other environmental settings. In the present study MeHg was orally gavaged to mice, at doses of 2.5, 5, and 10 mg/kg for 4 weeks. Fasting hyperglycemia, activity of hepatic phoshphoenolpyruvate carboxykinase and glucose 6-phoshphate were reported high as compared to control group. Inflammatory markers like, tumor necrosis factor α, the actual end product of inflammatory mediators' cascade pathway was also raised in comparison to control group. Hyperinsulinemia observed in serum showed clear understanding of mercury induced insulin resistance. Moreover, tissue damage due to increased oxidative stress markers like, hepatic lipid peroxidation, 8-deoxygunosine, reactive oxygen species, and carbonyl groups was significantly higher as compared to control group. MeHg caused a significant reduction in antioxidant markers like ferric reducing antioxidant power and total thiol molecules. The present study highlighted that activity of key enzymes involved in glucose metabolism is changed, owing to MeHg induced toxicity in the liver. Induction of similar toxic effects assumed to be stimulated by the production of high quantity free radicals.

Ambient PM2.5 caused depressive-like responses through Nrf2/NLRP3 signaling pathway modulating inflammation

PM2.5 pollution has been associated with numerous adverse effects including cardiovascular, respiratory and metabolic diseases as well as emotional disorders. However, the potential mechanism has not known clearly. Twenty-four rats were divided into 3 groups and exposed to various airs: filtered air (FA), unfiltered air (UA) and concentrated PM2.5 air (CA), respectively. Thirty wild type (WT) and 30 Nrf2 knockout (KO) mice were divided into 2 groups and exposed to FA and UA, respectively. The changes of neurobehavioral function, neurotransmitter secretion, toxic elements deposition, oxidative stress and the inflammation in prefrontal cortex were investigated during 9-12 weeks with/without PM2.5 exposure. Results showed that CA rats and KO-UA mice emerged obviously depressive-like responses. Li, Be, Al, Cr, Co, Ni, Se, Cd, Ba, Ti and Pb could deposit in the prefrontal cortex of rats after PM2.5 exposure. The neurotransmitters were significantly disorder in prefrontal cortex of CA rats. The NLRP3 signaling pathway was more activated in Nrf2^-/- than WT mice after PM2.5 exposure for 9 weeks. Nrf2/ NLRP3 signaling pathway modulating the inflammation might play an important role in the depression induced by ambient PM2.5.

Toxicological evaluation of airborne particulate matter. Are cell culture technologies ready to replace animal testing?

Exposure to atmospheric particulate matter (PM) can affect human health, causing asthma, atherosclerosis, renal disease and cancer. In the last few years, outdoor air pollution has increased globally, leading to a public health emergency. Epidemiological studies have reported a correlation between the development of severe respiratory and systemic diseases and exposure to PM. To evaluate the toxic effect of PM of different origins, conventional experimental toxicological investigations have been conducted in animals; however, animal experimentation poses major ethical issues and usually differs from human conditions. As an alternative, human cell cultures are increasingly being used to investigate cellular and molecular mechanisms of PM toxicity. Although 2D cell cultures have been proven helpful, they are far from being a valid alternative to animal tests. Recently, 3D cell culture and organ-on-chip technology have provided systems that are more complex and that can be more informative for toxicity studies. In this review, the results of the 2D systems that are most frequently used for PM toxicity evaluations are summarized with a special focus on their limitations. We also examined to which extent 3D cell culture and particularly the organ-on-chip technology may overcome these limitations and represent effective tools to improve airborne PM toxicity evaluations.

Using Nrf2/antioxidant response element-dependent signaling to assess the toxicity potential of fly ash particles

Epidemiological studies have demonstrated an association between ambient particulate pollution and adverse health effects in humans. The antioxidant-responsive element (ARE) cytoprotective system mediated by the transcription factor NF-E2 p45-related factor 2 (Nrf2) serves as a primary defense against the oxidative stress triggered by particulate matter. In this study, using a cell-based ARE-reporter assay, the fine fractions of the fly ash collected from the municipal solid waste incinerators at four cities in China were examined for their ability to activate Nrf2/ARE signaling. We found that, at a non-lethal dose, all the fly ash samples were able to activate the ARE-reporter gene in a dose- and redox-dependent manner, and this was correlated with their cytotoxicity and their ability to induce DNA damage. Study of the kinetics revealed that fly ash particles elicited a prolonged activation of the ARE-reporter activity. Upon exposure to the particles, the ARE-luciferase activity significantly increased in 2 h, reached a peak at 24 h, and remained high level at 72 h. This was in contrast to the transient activation of the ARE-reporter gene triggered by the Nrf2 activators tert-butylhydroquinone and sulforaphane, while ARE-luciferase activity dropped to the basal level at 72 h from the peak at 24 h. These results demonstrate the robustness of using cell-based ARE-reporter assays to evaluate the oxidative potential of fly ash. Our novel findings suggest that the sustained activation of the Nrf2/ARE signaling pathway induced by fly ash particles perturbs cellular redox homeostasis, which in turn contributes to toxicity.

Cytotoxicity comparison between fine particles emitted from the combustion of municipal solid waste and biomass

Fine particles (PM_2.5) emitted from municipal solid waste incineration (MSWI) contain high amounts of toxic compounds and pose a serious threat to environment and human health. In this study, entire particles as well as extracted water-soluble and -insoluble fractions of PM_2.5 collected from MSWI and biomass incineration (BMI) were subjected to physiochemical characterization and cytotoxic tests in A549 and BEAS-2B cells. MSWI PM_2.5 had higher contents of heavy metals (including Pb, Zn, and Cu) and dioxins (PCDD/Fs) than did BMI PM_2.5. The metals were enriched in the water-insoluble fraction, as measured by inductively coupled plasma-atomic emission spectrometry. BMI PM_2.5 had a higher content of endotoxin, which was also enriched in the water-insoluble fraction. MSWI PM_2.5 caused more serious cell injuries, as indicated by the lower viability, higher ROS generation, and DNA damage, whereas BMI PM_2.5 presented higher pro-inflammatory potential, as indicated by increased mRNA levels of interleukin 6. Normal human BEAS-2B cells were more sensitive than A549 cells in all these tests. Toxic effects caused by MSWI and BMI PM_2.5 were mostly attributable to their water-insoluble fractions. Our results indicate different chemical and biological compositions in MSWI and BMI PM_2.5 probably dominate in different toxic endpoints in vitro.

Using multi-integrated biomarker indexes approach to assess marine quality and health status of marine organism: a case study of Ruditapes philippinarum in Laizhou Bay, China

With the progress of technology and the deepening of understanding of biological monitoring, much more attention has been paid to the multiple evaluation of marine pollution monitoring. In view of this, our study aimed at establishing a multi-integrated biomarker indexes approach to evaluate marine condition systematically and comprehensively. In the current study, sampling was conducted in Laizhou Bay, China (S1, S2, and S3) in May, August, and October of 2015. And then, multi-integrated biomarker indexes approach was applied to assess marine PAHs pollution, select appropriate biomarkers, and evaluate marine environmental quality and health status of the clams of Ruditapes philippinarum. As the results showed, S2 was the most PAHs-polluted site while S1 was the least polluted site, and the levels of tPAHs in seawater and sediments ranged from 69.78 to 315.30 ng/L and 163.19 to 565.17 ng/g d.w., respectively. And all three sampling sites had different sources of PAHs. IBR represented DNA damage (F value), the expression of SOD, EROD activity, GST activity, and LPO could be served as biomarkers to monitor the PAHs pollution in Laizhou Bay. And MPI suggested the quality of all three sites: S1 was generally favorable, S2 was moderately polluted, and S3 was lightly polluted. BRI values showed that the order of health status of R. philippinarum was S1 > S3 > S2.

BMI1 Deficiency Results in Female Infertility by Activating p16/p19 Signaling and Increasing Oxidative Stress

The polycomb repressor B lymphoma Mo-MLV insertion region 1 (BMI1) is a core composition of polycomb repressive complex 1 (PRC1) and contributes to diverse fundamental cellular processes including cell senescence, apoptosis and proliferation. To investigate the role and mechanism of BMI1 in maintaining normal female reproductive function, we compared the differences in reproductive phenotypes between Bmi1-deficient and wild-type female mice. The Bmi1-deficient female mice were then supplemented with N-acetylcysteine in their drinking water to explore whether antioxidant supplementation could improve reproductive dysfunction caused by BMI1 deficiency. The results revealed that Bmi1 deletion resulted in complete infertility in female mice, estrous cycle disorder, and follicular developmental disorders. The reactive oxygen species levels in the ovarian tissue were increased; the ability of antioxidant enzymes was downregulated; the expression levels of p19 and p53 proteins were significantly upregulated. We also found that oocytes derived from Bmi1-deficient mice could not develop into embryos by in vitro fertilization and in vitro culture of embryos. Furthermore, supplementation with the antioxidant NAC not only improved the reproductive defects caused by Bmi1 deletion, but also largely rescued the ability of Bmi1-deficient oocytes to develop into embryos in vitro. These results indicated that cells lacking Bmi1 resulted in female infertility by activating the p16/p19 signaling pathway, increasing oxidative stress and DNA damage, inhibiting granulosa cell proliferation, and inducing granulosa cell apoptosis. Thus, BMI1 may be a novel potential target for the clinical treatment of female infertility.

Oxidative capacity and hemolytic activity of settled dust from moisture-damaged schools

Exposure to moisture-damaged indoor environments is associated with adverse respiratory health effects, but responsible factors remain unidentified. In order to explore possible mechanisms behind these effects, the oxidative capacity and hemolytic activity of settled dust samples (n = 25) collected from moisture-damaged and non-damaged schools in Spain, the Netherlands, and Finland were evaluated and matched against the microbial content of the sample. Oxidative capacity was determined with plasmid scission assay and hemolytic activity by assessing the damage to isolated human red blood cells. The microbial content of the samples was measured with quantitative PCR assays for selected microbial groups and by analyzing the cell wall markers ergosterol, muramic acid, endotoxins, and glucans. The moisture observations in the schools were associated with some of the microbial components in the dust, and microbial determinants grouped together increased the oxidative capacity. Oxidative capacity was also affected by particle concentration and country of origin. Two out of 14 studied dust samples from moisture-damaged schools demonstrated some hemolytic activity. The results indicate that the microbial component connected with moisture damage is associated with increased oxidative stress and that hemolysis should be studied further as one possible mechanism contributing to the adverse health effects of moisture-damaged buildings.

An ultra-high-performance liquid chromatography tandem mass spectrometry method for oxidative stress biomarker analysis in wastewater

Reported herein is the development of an analytical method for the detection of four oxidative stress biomarkers in wastewater using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and solid phase extraction (SPE). The following four biomarkers of oxidative stress and lipid peroxidation have been investigated: hydroxynonenal-mercapturic acid (HNE-MA), 8-iso-prostglandin F2beta (8-iso-PGF_2β), 8-nitroguanine (8-NO₂Gua) and 8-hydroxy-2-deoxyguanosine (8-OHdG). The method showed very good performance: accuracy (> 87%), precision (> 90%), method quantification limits (1.3-3.0 ng L^-1) and biomarker stability in wastewater in the case of HNE-MA, 8-OHdG and 8-iso-PGF_2β. In contrast, 8-NO₂Gua was found to be less stable in wastewater, which affected its method performance: accuracy (> 63%), precision (> 91%) and method quantification limits (85.3 ng L^-1). Application of the developed method resulted in, for the first time, HNE-MA being successfully observed and quantified within wastewater over a study period of a week (displayed average daily loads per capita of 48.9 ± 4.1 mg/1000/people/day). 8-iso-PGF_2β was detected with good intensity but could not be quantified due to co-elution with other isomers. 8-OHdG was detected, albeit at < MQL. This study demonstrates the potential for expanding on the possible endogenous biomarkers of health used in urban water fingerprinting to aid in measuring health in near-real time on a community-wide scale.

Protective effects of α-lipoic acid on cultured human nasal fibroblasts exposed to urban particulate matter

BACKGROUND

Exposure to urban particulate matter (UPM) has been studied as a cause of various health problems. Although the association between UPM and the respiratory tract has been well studied, further research is required to characterize the effects of UPM on the upper respiratory tract. We investigated the effects of UPM-induced reactive oxygen species (ROS) production on cultured human nasal fibroblasts, as well as the protective effects of α-lipoic acid (ALA) on ROS production and the underlying signaling pathways involved in ROS inhibition.

METHODS

Human turbinate tissue specimens were collected from 6 patients. The effects of UPM on the viability of cultured nasal fibroblasts were determined. A fluorescent malondialdehyde assay was used to measure ROS levels. Real-time reverse transcription polymerase chain reaction was used to measure the messenger RNA levels of genes encoding Nrf2, the antioxidant response elements (AREs) (HO-1, NQO1), and the proinflammatory cytokines (interleukin-6 and interleukin-8) before and after ALA treatment. Western blotting analyses were used to measure nuclear and cytosolic Nrf2 and AREs.

RESULTS

UPM reduced cell viability and increased ROS expression in nasal fibroblasts. ALA treatment decreased ROS production in UPM-exposed fibroblasts via the Nrf2, HO-1, and NQO-1 pathways. Also, ALA treatment abrogated increases in the interleukin-6 and -8 levels induced by UPM in nasal fibroblasts.

CONCLUSION

UPM exposure resulted in increased ROS production in nasal fibroblasts. ALA treatment inhibited this increase via the Nrf2 pathway, suggesting that ALA may have a protective effect against rhinitis caused by ROS expression induced by exposure to UPM.

A comparison of poly-ethylene-glycol-coated and uncoated gold nanoparticle-mediated hepatotoxicity and oxidative stress in Sprague Dawley rats

Background

Gold nanoparticles (GNPs) and their functional derivatives are of great interest because of their many biomedical applications. GNPs are increasingly being incorporated into new diagnostic and therapeutic approaches in medicine. Consequently, there has been a strong push to fully understand their interactions with blood components. The agglomeration of cells reflects the interaction of nanoparticles with blood components.

Methods

The main aim of this study was to compare the effects of poly-ethylene-glycol (PEG)-oated and uncoated GNPs on the generation of reactive oxygen species (ROS); on the actions of distinct hepatotoxicity biomarkers such as alanine (ALT) and aspartate (AST) aminotransferases, and alkaline phosphatase (ALP); and on the histology of liver tissues in the rat model. Four distinct doses of PEG-coated and uncoated GNPs (12.5, 25, 50, and 100 µg/kg body weight) were used. Each group consisted of three rats receiving an oral administration of PEG-coated and uncoated GNPs for 5 days with one dose per 24 hours. The control group consisted of three rats that received deionized water. Twenty-four hours after the last treatment, samples were collected following standard procedures.

Results

PEG-coated and uncoated GNPs enhanced the generation of ROS and the activity of serum aminotransferases (ALT/AST) and ALPs relative to the negative control. A liver histology assessment of GNP-exposed rats revealed statistically significant responses in the variation of the morphologies of tissues relative to those of the negative control. Nonetheless, uncoated GNPs demonstrated enhanced hepatotoxic outcomes relative to those of PEG-coated GNPs. The results demonstrated that both GNPs may be able to promote hepatotoxicity in Sprague Dawley rats through mechanisms of oxidative stress. However, uncoated GNPs have more harmful effects than PEG-coated GNPs relative to the negative control.

Conclusion

Taken together, the results of this study indicate that PEG-coated GNPs may be safer to use in nanomedicinal applications than uncoated GNPs. However, more studies must be performed to confirm the outcomes of PEGylation.

Ambient wintertime particulate air pollution and hypertensive disorders of pregnancy in Monroe County, New York

BACKGROUND

Previous studies have reported associations between ambient fine particle (PM_2.5) concentrations and hypertensive disorders of pregnancy (HDP). However, none have examined whether ultrafine particles (UFP; < 100 nm), accumulation mode particles (AMP; 100-500 nm), markers of traffic pollution (black carbon; BC), or wood burning (Delta-C; (30% of ambient wintertime PM_2.5 in Monroe County, NY is from wood burning)) are associated with an increased odds of HDP. We estimated the odds of HDP associated with increased concentrations of PM_2.5, UFP, AMP, BC, and Delta-C in each gestational month during winter months.

METHODS

Electronic medical records and birth certificate data were linked with land-use regression models in Monroe County, New York in 2009-2013 to predict monthly pollutant concentrations during winter (November-April) based on maternal residential address for 16,637 births. Using multivariable logistic regression, we estimated the odds of HDP associated with each interquartile range (IQR) increase in PM_2.5, UFP, AMP, BC, and Delta-C concentrations during each gestational month, adjusting for maternal characteristics, birth hospital, temperature, and relative humidity.

RESULTS

Each 0.52 µg/m³ increase in Delta-C concentration during the 7th gestational month was associated with an increased odds of HDP (odds ratio (OR) = 1.21; 95% confidence interval (CI) = 1.01, 1.45), with a similar sized estimate in month 8 (OR = 1.18; 95%CI = 0.98, 1.43). Non-statistically significant increased odds of HDP associated with IQR increases in BC concentrations during months 3 (OR = 1.12; 95%CI = 0.98, 1.28) and 7 (OR = 1.12; 95%CI = 0.96, 1.29) were observed. Increased odds of HDP were not observed for PM_2.5, UFP, or AMP.

CONCLUSIONS

Our findings suggest that maternal exposure to wood smoke in Monroe County during winter is associated with an increased odds of HDP during late gestation. Additional studies are needed to evaluate the effect of wood smoke on HDP and to explore effects on other pregnancy outcomes.

Ambient urban dust particulate matter reduces pathologic T cells in the CNS and severity of EAE

BACKGROUND

Autoimmune diseases have increased in incidence and prevalence worldwide. While genetic predispositions play a role, environmental factors are a major contributor. Atmospheric particulate matter (PM) is a complex mixture composed of metals, nitrates, sulfates and diverse adsorbed organic compounds like polycyclic aromatic hydrocarbons (PAHs) and dioxins. Exposure to atmospheric PM aggravates autoimmune diseases such as type 1 diabetes, rheumatoid arthritis, multiple sclerosis, and systemic lupus erythematosus, among others. PAHs and dioxins are known aryl hydrocarbon receptor (AHR) ligands. The AHR modulates T cell differentiation and directs the balance between effector and regulatory T cells in vitro and in experimental autoimmune encephalomyelitis (EAE), a murine model of autoimmune disease. This study aims to identify pathways that contribute to autoimmune disease and their potential use as therapeutic targets to alleviate symptoms and the need for global immunosuppression. This study tests the hypothesis that atmospheric PM enhances effector T cell differentiation and aggravates autoimmune disease.

RESULTS

An atmospheric ambient urban dust PM sample, standard reference material (SRM)1649b, was tested for its effects on autoimmunity. SRM1649b PM enhanced Th17 differentiation in an AHR-dependent manner in vitro, however intranasal treatment of SRM1649b PM delayed onset of EAE and reduced cumulative and peak clinical scores. Chronic and acute intranasal exposure of SRM1649b PM delayed onset of EAE. Chronic intranasal exposure did not reduce severity of EAE while acute intranasal exposure significantly reduced severity of disease. Acute intranasal treatment of low dose SRM1649b PM had no effect on clinical score or day of onset in EAE. Delayed onset of EAE by intranasal SRM1649b PM was AHR-dependent in vivo. Oral gavage of SRM1649b PM, in the absence of AHR ligands in the diet, had no effect on day of disease onset or severity of EAE. Day 10 analysis of T cells in the CNS after intranasal treatment of SRM1649b PM showed a reduction of pathologic T cell subsets in vivo. Moreover, MOG-specific splenocytes require AHR to generate or maintain IL-10 producing cells and reduce IFNγ producing cells in vitro.

CONCLUSIONS

These results identify the AHR pathway as a potential target for driving targeted immunosuppression in the CNS in the context of atmospheric PM-mediated autoimmune disease. The effects of SRM1649b PM on EAE are dependent on route of exposure, with intranasal treatment reducing severity of EAE and delaying disease onset while oral gavage has no effect. Intranasal SRM1649b PM reduces pathologic T cells in the CNS, specifically Th1 cells and Th1Th17 double positive cells, leading to reduced severity of EAE and AHR-dependent delayed disease onset. Additionally, SRM1649b PM treatment of antigen-specific T cells leads to AHR-dependent increase in percent IL-10 positive cells in vitro. These findings may shed light on the known increase of infection after exposure to atmospheric PM and serve as the first step in identifying components of the AHR pathway responsible for Th1-mediated immunosuppression in response to atmospheric PM exposure.

Association of Exposure to Fine-Particulate Air Pollution and Acidic Gases with Incidence of Nephrotic Syndrome

Background: Air pollution has been associated with autoimmune diseases. Nephrotic syndrome is a clinical manifestation of immune-mediated glomerulopathy. However, the association between nephrotic syndrome and air pollution constituents remains unknown. We conducted this nationwide retrospective study to investigate the association between PM_2.5 and nephrotic syndrome. Methods: We used the Longitudinal Health Insurance Database (LHID) and the Taiwan Air Quality-Monitoring Database (TAQMD). We combined and stratified the LHID and the TAQMD data by residential areas of insurants linked to nearby air quality-monitoring stations. Air pollutant concentrations were grouped into four levels based on quartile. Univariable and multivariable Cox proportional hazard regression models were applied. Findings: Relative to Q1-level SO₂, subjects exposed to the Q4 level were associated with a 2.00-fold higher risk of nephrotic syndrome (adjusted HR = 2.00, 95% CI = 1.66⁻2.41). In NOx, relative to Q1 NOx concentrations, the adjusted HRs of nephrotic syndrome risk were 1.53 (95% CI = 1.23⁻1.91), 1.30 (95% CI = 1.03⁻1.65), and 2.08 (95% CI = 1.69⁻2.56) for Q2, Q3, and Q4 levels, respectively. The results revealed an increasing trend for nephrotic syndrome risk correlating with increasing levels of NO, NO₂, and PM_2.5 concentrations. Interpretation: High concentrations of PM_2.5, NO, NO₂, and SO₂ are associated with increased risk of nephrotic syndrome.

Cardiac and pulmonary toxicity of mesoporous silica nanoparticles is associated with excessive ROS production and redox imbalance in Wistar rats

Mesoporous silica nanoparticles (MSNs) represent one of the most promising drug delivery systems. MSNs have attracted considerable attention in recent years both in industry and biomedicine due to their unique properties. Thus, evaluation of the toxic effects of MSNs is necessary before the biomedical and clinical applications. We investigated the in vivo effect of MSNs on the production of reactive oxygen species (ROS), antioxidant defenses and histology of the heart and lung. Rats received 25, 50, 100 and 200 mg/kg body weight of synthesized MSNs intraperitoneally for 30 days and samples were collected for analysis. MSNs induced significant increase in serum cardiac function markers, tumor necrosis factor alpha and lipids. MSNs-induced rats exhibited anemia, thrombocytopenia, leukocytosis, significantly increased ROS, malondialdehyde and nitric oxide, and declined antioxidant defenses in the heart and lung of rats. In addition, MSNs induced histological alterations in the heart and lung of rats. In conclusion, our results demonstrated that MSNs induce cardiotoxicity and pulmonary toxicity via excessive generation of ROS, suppressed antioxidants, inflammation and histological alterations. Further investigations are recommended to understand the molecular mechanism underlying the toxic effects of MSNs and to improve the performance of nanomedicine.

Effect of nitroso-redox imbalance on male reproduction

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are byproducts of normal metabolic processes. They are necessary for normal cellular function and are kept in balance by antioxidant mechanisms. Alterations in levels of ROS and RNS can lead to nitroso-redox imbalance that in turn can negatively affect male reproduction. Strategies to decrease ROS/RNS involve evasion of exposures (smoking, meat intake, pollution, calorie-dense diet), managing lifestyle, and increasing the consumption of antioxidants (vitamin C, vitamin E, alpha-lipoic acid, taurine, quercetin). Targeted therapies focusing on nitroso-redox imbalance can be critical for treatment of male reproductive dysfunction. This review outlines endogenous and exogenous sources of ROS/RNS, adverse effect on male reproduction, and strategies to control nitroso-redox imbalance.

Using a glucose meter to quantitatively detect disease biomarkers through a universal nanozyme integrated lateral fluidic sensing platform

Along with the advance in medical research, more biomarkers emerge as useful indicators for both disease and health index. However, majority of them have no practical or economic testing methods available yet, or rely on high-costing methods such as Enzyme-Linked Immuno-Sorbent Assay (ELISA), High-Performance Liquid Chromatography (HPLC), Mass Spectrum, and immunohistochemistry (IHC). In this article, we develop a universal nanozyme integrated testing platform for biological molecules that incorporates the electrochemical measurement of glucose with lateral flow immunostrip (LFS) for target analytes. This design involves the quantitative conversion of analytes into invertase and then glucose, which can be measured by an extremely affordable meter. The feasibility of this design was validated using 8-hydroxy-2'-deoxyguanosine (8-OHdG) and prostate specific antigen (PSA) as representatives for small molecules and moderate to large proteins respectively. Our approach yields results comparable to commercial diagnostic ELISA kits at a substantially reduced cost and reaction time. Specifically, the design has a detection limit of 0.23 ng mL^-1 for 8-OHdG and 1.26 ng mL^-1 for PSA, and a detection range of 0.1-100 ng mL^-1 for 8-OHdG and 1-100 ng mL^-1 for PSA. By combining the accessibility of well-established glucose testing and LFS, our design can serve as a point of care testing method that can be fully integrated into the personal lifestyle without requiring professional assistance.

Impact of Maternal Air Pollution Exposure on Children's Lung Health: An Indian Perspective

Air pollution has become an emerging invisible killer in recent years and is a major cause of morbidity and mortality globally. More than 90% of the world’s children breathe toxic air every day. India is among the top ten most highly polluted countries with an average PM₁₀ level of 134 μg/m³ per year. It is reported that 99% of India’s population encounters air pollution levels that exceed the World Health Organization Air Quality Guideline, advising a PM_2.5 permissible level of 10 μg/m³. Maternal exposure to air pollution has serious health outcomes in offspring because it can affect embryonic phases of development during the gestation period. A fetus is more prone to effects from air pollution during embryonic developmental phases due to resulting oxidative stress as antioxidant mechanisms are lacking at that stage. Any injury during this vulnerable period (embryonic phase) will have a long-term impact on offspring health, both early and later in life. Epidemiological studies have revealed that maternal exposure to air pollution increases the risk of development of airway disease in the offspring due to impaired lung development in utero. In this review, we discuss cellular mechanisms involved in maternal exposure to air pollution and how it can impact airway disease development in offspring. A better understanding of these mechanisms in the context of maternal exposure to air pollution can offer a new avenue to prevent the development of airway disease in offspring.

Cancer Risk from Exposure to Particulate Matter and Ozone According to Obesity and Health-Related Behaviors: A Nationwide Population-Based Cross-Sectional Study

BACKGROUND

There is little evidence of an association between cancer risk and long-term exposure to ambient particulate matter <10 μm (PM₁₀) and ozone (O₃), according to obesity and health-related behaviors.

METHODS

In the 2012 Korean Community Health Survey, survey data on socioeconomic characteristics, health-related behaviors, and previous cancer history were collected from 100,867 participants. Daily average concentrations of PM₁₀ and O₃ (2003-2012) were obtained from the Korean Air Pollutants Emission Service. The cancer risks for interquartile increases in PM₁₀ and O₃ were evaluated using multiple logistic regression and were stratified by age, sex, obesity, and health-related behaviors.

RESULTS

Increased cancer risk was found among obese subjects aged ≥50 years after adjusting for confounding factors [PM₁₀: ≥60 years: OR 1.34, 95% confidence interval (CI) 1.03-1.74; 50-60 years: OR 1.40, CI 1.01-1.96; O₃: ≥60 years: OR 1.12, CI 1.04-1.20; 50-60 years: OR 1.20, CI 1.08-1.33]. However, we did not observe similar trends in the nonobese subjects. Among obese subjects aged ≥50 who had been exposed to PM₁₀, men, ever smokers, and inactive subjects were at increased cancer risk. Regarding O₃, the cancer risk was significantly higher among obese adults >50 years old, regardless of sex or health-related behaviors.

CONCLUSIONS

Long-term exposure to PM₁₀ and O₃ was found to increase cancer risk. In particular, the risk differed according to obesity status, age, sex, and health-related behaviors.

IMPACT

The effect of air pollution on cancer risk was compounded by obesity, smoking, and physical inactivity among subjects over 50 years old.

Particulate matter air pollution components and incidence of cancers of the stomach and the upper aerodigestive tract in the European Study of Cohorts of Air Pollution Effects (ESCAPE)

INTRODUCTION

Previous analysis from the large European multicentre ESCAPE study showed an association of ambient particulate matter <2.5 μm (PM_2.5) air pollution exposure at residence with the incidence of gastric cancer. It is unclear which components of PM are most relevant for gastric and also upper aerodigestive tract (UADT) cancer and some of them may not be strongly correlated with PM mass. We evaluated the association between long-term exposure to elemental components of PM_2.5 and PM₁₀ and gastric and UADT cancer incidence in European adults.

METHODS

Baseline addresses of individuals were geocoded and exposure was assessed by land-use regression models for copper (Cu), iron (Fe) and zinc (Zn) representing non-tailpipe traffic emissions; sulphur (S) indicating long-range transport; nickel (Ni) and vanadium (V) for mixed oil-burning and industry; silicon (Si) for crustal material and potassium (K) for biomass burning. Cox regression models with adjustment for potential confounders were used for cohort-specific analyses. Combined estimates were determined with random effects meta-analyses.

RESULTS

Ten cohorts in six countries contributed data on 227,044 individuals with an average follow-up of 14.9 years with 633 incident cases of gastric cancer and 763 of UADT cancer. The combined hazard ratio (HR) for an increase of 200 ng/m³ of PM_2.5_S was 1.92 (95%-confidence interval (95%-CI) 1.13;3.27) for gastric cancer, with no indication of heterogeneity between cohorts (I² = 0%), and 1.63 (95%-CI 0.88;3.01) for PM_2.5_Zn (I² = 70%). For the other elements in PM_2.5 and all elements in PM₁₀ including PM₁₀_S, non-significant HRs between 0.78 and 1.21 with mostly wide CIs were seen. No association was found between any of the elements and UADT cancer. The HR for PM_2.5_S and gastric cancer was robust to adjustment for additional factors, including diet, and restriction to study participants with stable addresses over follow-up resulted in slightly higher effect estimates with a decrease in precision. In a two-pollutant model, the effect estimate for total PM_2.5 decreased whereas that for PM_2.5_S was robust.

CONCLUSION

This large multicentre cohort study shows a robust association between gastric cancer and long-term exposure to PM_2.5_S but not PM₁₀_S, suggesting that S in PM_2.5 or correlated air pollutants may contribute to the risk of gastric cancer.

In-ovo exposed carbon black nanoparticles altered mRNA gene transcripts of antioxidants, proinflammatory and apoptotic pathways in the brain of chicken embryos

With ubiquitous applications of nanotechnology, there are increasing probabilities of exposure to manufactured nanoparticles (NPs), which might be posing emerging health concerns on the next generation. Recent data suggest that generation of reactive oxygen species may play an integral role in the carbon black nanoparticles (CBNPs)-induced oxidative injury; however, the exact molecular mechanism has not been clarified. Hence, the role of oxidative stress, inflammation and apoptosis pathways in the CBNPs-induced neuronal toxicity following in-ovo exposure of chicken embryo was elucidated. Specific pathogen-free fertilized Sasso eggs were inoculated with 4.8, 9.5 and 14 μg CBNPs/egg at the 3rd day of incubation alongside vehicle controls. In a concentration-dependent manner, CBNPs inoculation induced oxidative stress, which was ascertained by enhancement of lipid peroxides and diminishing total antioxidant capacity and glutathione levels, and catalase activity in brain tissues. mRNA transcript levels of antioxidant genes showed up-regulation of heme oxygenase-1 and superoxide dismutase-1, with marked down-regulation of glutathione S-transferase-α. Additionally, the pro-inflammatory genes; nuclear factor-κB1 was up-regulated, while interferon-γ was down-regulated. There is also a clear down-regulation in apoptotic markers caspase-8, caspase-3, cytochrome c and B-cell CLL/lymphoma 2 at the different concentrations, while caspase-2 is up-regulated only at higher concentration. Collectively, these results show that CBNPs exposure-mediated overproduction of the free radicals, particularly at higher concentration contributes to inflammation and subsequent cellular apoptosis at the gene expression level, thus unveiling possible molecular relationship between CBNPs and genes linked to the oxidant, inflammatory and apoptotic responses.

Genotoxic and epigenotoxic effects in mice exposed to concentrated ambient fine particulate matter (PM2.5) from São Paulo city, Brazil

BACKGROUND

The Metropolitan Area of São Paulo has a unique composition of atmospheric pollutants, and positive correlations between exposure and the risk of diseases and mortality have been observed. Here we assessed the effects of ambient fine particulate matter (PM2.5) on genotoxic and global DNA methylation and hydroxymethylation changes, as well as the activities of antioxidant enzymes, in tissues of AJ mice exposed whole body to ambient air enriched in PM2.5, which was concentrated in a chamber near an avenue of intense traffic in São Paulo City, Brazil.

RESULTS

Mice exposed to concentrated ambient PM2.5 (1 h daily, 3 months) were compared to in situ ambient air exposed mice as the study control. The concentrated PM2.5 exposed group presented increased levels of the oxidized nucleoside 8-oxo-7,8-dihydro-2'-deoxyguanosine in lung and kidney DNA and increased levels of the etheno adducts 1,N6-etheno-2'-deoxyadenosine and 1,N2-etheno-2'-deoxyguanosine in kidney and liver DNA, respectively. Apart from the genotoxic effects, the exposure to PM2.5 led to decreased levels of the epigenetic mark 5-hydroxymethylcytosine (5-hmC) in lung and liver DNA. Changes in lung, liver, and erythrocyte antioxidant enzyme activities were also observed. Decreased glutathione reductase and increased superoxide dismutase (SOD) activities were observed in the lungs, while the liver presented increased glutathione S-transferase and decreased SOD activities. An increase in SOD activity was also observed in erythrocytes. These changes are consistent with the induction of local and systemic oxidative stress.

CONCLUSIONS

Mice exposed daily to PM2.5 at a concentration that mimics 24-h exposure to the mean concentration found in ambient air presented, after 3 months, increased levels of DNA lesions related to the occurrence of oxidative stress in the lungs, liver, and kidney, in parallel to decreased global levels of 5-hmC in lung and liver DNA. Genetic and epigenetic alterations induced by pollutants may affect the genes committed to cell cycle control, apoptosis, and cell differentiation, increasing the chance of cancer development, which merits further investigation.

Anti-cancer effects of 3,5-dimethylaminophenol in A549 lung cancer cells

Exposure to 3,5-dimethylaminophenol (3,5-DMAP), the metabolite of the 3-5-dimethylaniline, was shown to cause high levels of oxidative stress in different cells. The aim of the present work was to observe whether this metabolite can lead to cytotoxicity, oxidative stress, DNA damage and cell cycle changes in non-small cell lung cancer A549 cells. 3,5-DMAP caused a dose-dependent increase in cytotoxicity, generation of superoxide (O₂^-.), inductions in the enzyme activities orchestrating cellular antioxidant balance, increases in lipid peroxidation as well as DNA damage. However, 3,5-DMAP showed significantly lower cytotoxicity towards human lung fibroblast (HLF) cells. 3,5-DMAP also led to molecular events, like inducing apoptotic markers (ie. p53, Bad, Bax and cytochrome c); decreasing anti-apoptotic proteins (Bcl-2) and alterations in cell cycle. Our findings indicate that the cytotoxicity caused by this particular alkylaniline metabolite led to initiation of caspase 3-mediated apoptosis. Furthermore, 3,5-DMAP attenuated carcinogenic properties like migration capacity of A549 cells and eventually inhibited growth of A549 cells in an in vivo mouse model. Tumor sections showed that 3,5-DMAP down-regulated c-Myc expression but up-regulated p53 and cytochrome c, all of which might result in tumor growth arrest. Co-treatment with N-acetylcysteine provided reductions in cytotoxicity and positively modulated genetic events induced by 3,5-DMAP in A549 cells. In conclusion, our findings demonstrate 3,5-DMAP may be a potential anti-cancer drug in cancer, due to its self redox cycling properties.

Genotoxic and cytotoxic properties of PM2.5 collected over the year in Wrocław (Poland)

In the ambient is >2000 chemical substances, some of them are absorbed on the surface of the particulate matter and may causes many health problems. Air pollution is responsible for >3.2 million premature deaths which classifies it as a second place environmental risk factor. Especially dangerous for health are polycyclic aromatic hydrocarbons and their derivatives which shows mutagenic and carcinogenic properties. Air pollutions were also classified by International Agency for Research on Cancer to group which carcinogenic properties on human were proved by available knowledge. Air pollutions, are one of the biggest problem in Polish cities. The article presents results of mutagenicity, genotoxicity and cytotoxicity researches conducted on a particulate matter fraction 2.5 μm collected during all year long in Wroclaw agglomeration (Poland). The material was collected on filters using high-flow air aspirator and extracted using dichloromethane. Additionally it was fractionated into 4 parts containing: all pollutants, only polycyclic aromatic hydrocarbons, nitro derivatives of PAHs and dinitro derivatives of PAHS. Dry residue of this fraction was dissolving in DMSO and tested using biological methods. Biological methods include mutagenicity properties which are investigated by Salmonella assay (Ames assay). Other biological method was comet assay and 4 parameter cytotoxicity test PAN-I assay. Results of the conducted experiments show differences in mutagenic, genotoxic and cytotoxic properties between seasons of collection and between volumes of dust pollutions fractions. The worst properties shows particles collected in autumn and winter season Results showed also some correlations in results obtained during different methods and properties. Due to the limited possibilities of testing all chemical compounds present in the PM2.5 fraction, it is recommended to carry out tests based on a set of genotoxic and cytotoxic tests, which is confirmed by the conducted research.

The association between ambient air pollution exposure and mental health status in Chinese female college students: a cross-sectional study

The association between exposure to air pollution and mental health has not been adequately studied. Accordingly, this study aimed to explore the association between exposure to ambient air pollution and mental health status among female college students. We performed a cross-sectional study involving female students attending college located in Anshan, a heavy industry city in Northeast China. The investigation was performed using electronic questionnaires including the Symptom Checklist-90 (SCL-90), Pittsburgh Sleep Quality Index (PSQI), Cornell Medical Index (CMI), and general well-being (GWB) scale between March and April 2017. The individual daily average of time spent outdoors in each season was used as an indicator of exposure to ambient air pollution. The association between mental health status and exposure to ambient air pollution was analyzed using general linear regression. Of the 412 female participants, 346 (83.98%) submitted valid questionnaires. Multivariate linear regression indicated that GWB was negatively associated with the SCL-90 score, and annual average daily outdoor time and sleep quality were positively associated with the SCL-90 score. This study demonstrated that exposure to ambient air pollution may be a risk factor for mental health problems among female college students.

Air pollution exposure during pregnancy and spontaneous abortion and stillbirth

The developing fetus is particularly susceptible to environmental pollutants, and evidence has shown adverse effects of air pollutants on pregnancy and birth outcomes. Pregnancy loss, including spontaneous abortion (miscarriage) and stillbirth, is the most severe adverse pregnancy outcome. This review focuses on air pollution exposure during pregnancy in relation to spontaneous abortion and stillbirth. A total of 43 studies are included in this review, including 35 human studies and eight animal studies. Overall, these studies suggest that exposure to air pollutants such as particulate matter (PM), carbon monoxide (CO) and cooking smoke may be associated with higher risk for stillbirth and spontaneous abortion. PM₁₀ exposure during an entire pregnancy was associated with increased risk of spontaneous abortion, and exposure to PM_2.5 and PM₁₀ in the third trimester might increase the risk of stillbirth. CO exposure during the first trimester of pregnancy was associated with an increased risk of spontaneous abortion and exposure during the third trimester was associated with an increased risk of stillbirth. Cooking smoke was found to increase the risk of stillbirths, and the evidence was consistent. Insufficient and conflicting evidence was found for various other pollutants, such as NO₂ and SO₂. Studies did not show clear evidence for associations between pregnancy loss and others pollutants such as heavy metals, organochlorine compounds, PAH and total dust count. Further research is warranted to better understand the relationship between air pollution exposure and pregnancy loss.

Anthracene drives sub-cellular proteome-wide alterations in the degradative system of Penicillium oxalicum

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in polluted environments and are included in the priority list of toxic compounds. Previous studies have shown that the fungus Penicillium oxalicum, isolated from a hydrocarbon-polluted pond, has a great capability to transform different PAHs in short periods under submerged fermentation conditions. Although cytochrome p450s (CYPs) seems to be the main responsible enzyme in this process, changes in proteome profile remains poorly understood. The aim of this work was to characterise molecular disturbances in the cytosolic and microsomal sub-proteomes of P. oxalicum by applying two-dimensional (2D) gel electrophoresis and label-free quantitative proteomics during anthracene biodegradation. Our results showed that by using 2D-gels, 10 and 8 differential proteins were over-expressed in the cytosolic and microsomal fractions, respectively. Most of them were related to stress response. Shotgun proteomics allowed the identification of 158 and 174 unique protein species that differentially accumulated during anthracene biotransformation, such as CYPs, epoxide hydrolases and transferases enzymes, belonging to Phase I and Phase II of the metabolism of xenobiotics, contributing to the anthracene biodegradation pathway. These results confirm the biological significance of ascomycetes fungi the rol of CYPs on biodegradation and the need of a deeper knowledge on fungal proteomics for the application of the appropriate microorganisms in biodegradation processes.

Long-term effects of air pollution on ankle-brachial index

BACKGROUND

Ankle-brachial index (ABI) has been linked to the risk of cardiovascular events. However, the association between long-term exposure to air pollution and abnormal ABI has not been fully investigated.

METHODS

This cross-sectional study involved 4544 participants from the KORA Study (2004-2008) in the region of Augsburg, Germany. Participants' residential annual mean concentrations of particulate matter (PM) and nitrogen dioxide (NO₂) were predicted with land-use regression models, and the traffic information was collected from geographic information systems. We applied multinomial logistic regression models to assess the effects of air pollution on the prevalence of low and high ABI, and quantile regression models to explore the non-monotonic relationship between air pollution and ABI. We also examined effect modification by individual characteristics.

RESULTS

Long-term exposure to PM with an aerodynamic diameter ≤ 10 μm (PM₁₀) and ≤ 2.5 μm (PM_2.5) was significantly associated with a higher prevalence of low ABI, with the respective odds ratios (ORs) of 1.82 (95%CI: 1.11-2.97) and 1.59 (95%CI: 1.01-2.51) for a 5th to 95th percentile increment in pollutants. Positive associations with the prevalence of high ABI were observed for PM (e.g., PM₁₀: OR = 1.63, 95%CI: 1.07-2.50) and NO₂ (OR = 1.84, 95%CI: 1.15-2.94). Quantile regression analyses revealed similar non-monotonic results. The effects of air pollution on having abnormal ABI were stronger in physically inactive, hypertensive, or non-diabetic participants.

CONCLUSIONS

Long-term exposure to PM and NO₂ was associated with a higher prevalence of both low and high ABI, indicating the adverse effects of air pollution on atherosclerosis and arterial stiffness in the lower extremities.

Toxicoproteomic analysis of human lung epithelial cells exposed to steel industry ambient particulate matter (PM) reveals possible mechanism of PM related carcinogenesis

Toxicoproteomic analysis of steel industry ambient particulate matter (PM) that contain high concentrations of PAHs and metals was done by treating human lung cancer cell-line, A549 and the cell lysates were analysed using quantitative label-free nano LC-MS/MS. A total of 18,562 peptides representing 1576 proteins were identified and quantified, with 196 proteins had significantly altered expression in the treated cells. Enrichment analyses revealed that proteins associated to redox homeostsis, metabolism, and cellular energy generation were inhibited while, proteins related to DNA damage and repair and other stresses were over expressed. Altered activities of several tumor associated proteins were observed. Protein-protein interaction network and biological pathway analysis of these differentially expressed proteins were carried out to obtain a systems level view of proteome changes. Together it could be inferred that PM exposure induced oxidative stress which could have lead into DNA damage and tumor related changes. However, lowering of cellular metabolism, and energy production could reduce its ability to overcome these stress. This kind of disequilibrium between the DNA damage and ability of the cells to repair the DNA damage may lead into genomic instability that is capable of acting as the driving force during PM induced carcinogenesis.

Toxicological status of nanoparticles: What we know and what we don't know

The field of nanotechnology has grown exponentially during the last few decades, due in part to the use of nanoparticles in many manufacturing processes, as well as their potential as clinical agents for treatment of diseases and for drug delivery. This has created several new avenues by which humans can be exposed to nanoparticles. Unfortunately, investigations assessing the toxicological impacts of nanoparticles (i.e. nanotoxicity), as well as their possible risks to human health and the environment, have not kept pace with the rapid rise in their use. This has created a gap-in-knowledge and a substantial need for more research. Studies are needed to help complete our understanding of the mechanisms of toxicity of nanoparticles, as well as the mechanisms mediating their distribution and accumulation in cells and tissues and their elimination from the body. This review summarizes our knowledge on nanoparticles, including their various applications, routes of exposure, their potential toxicity and risks to human health.

Causation by Diesel Exhaust Particles of Endothelial Dysfunctions in Cytotoxicity, Pro-inflammation, Permeability, and Apoptosis Induced by ROS Generation

Epidemiological studies suggest that an increase of diesel exhaust particles (DEP) in ambient air corresponds to an increase in hospital-recorded myocardial infarctions within 48 h after exposure. Among the many theories to explain this data are endothelial dysfunction and translocation of DEP into vasculature. The mechanisms for such DEP-induced vascular permeability remain unknown. One of the major mechanisms underlying the effects of DEP is suggested to be oxidative stress. Experiments have shown that DEP induce the generation of reactive oxygen species (ROS), such as superoxide anion and H₂O₂ in the HUVEC tube cells. Transcription factor Nrf2 is translocated to the cell nucleus, where it activates transcription of the antioxidative enzyme HO-1 and sequentially induces the release of vascular permeability factor VEGF-A. Furthermore, a recent study shows that DEP-induced intracellular ROS may cause the release of pro-inflammatory TNF-α and IL-6, which may induce endothelial permeability as well by promoting VEGF-A secretion independently of HO-1 activation. These results demonstrated that the adherens junction molecule, VE-cadherin, becomes redistributed from the membrane at cell-cell borders to the cytoplasm in response to DEP, separating the plasma membranes of adjacent cells. DEP were occasionally found in endothelial cell cytoplasm and in tube lumen. In addition, the induced ROS is cytotoxic to the endothelial tube-like HUVEC. Acute DEP exposure stimulates ATP depletion, followed by depolarization of their actin cytoskeleton, which sequentially inhibits PI3K/Akt activity and induces endothelial apoptosis. Nevertheless, high-dose DEP augments tube cell apoptosis up to 70 % but disrupts the p53 negative regulator Mdm2. In summary, exposure to DEP affects parameters influencing vasculature permeability and viability, i.e., oxidative stress and its upregulated antioxidative and pro-inflammatory responses, which sequentially induce vascular permeability factor, VEGF-A release and disrupt cell-cell junction integrity. While exposure to a low dose of DEP actin triggers cytoskeleton depolarization, reduces PI3K/Akt activity, and induces a p53/Mdm2 feedback loop, a high dose causes apoptosis by depleting Mdm2. Addition of ROS scavenger N-acetyl cysteine suppresses DEP-induced oxidative stress efficiently and reduces subsequent damages by increasing endogenous glutathione.

Fine Particulate Air Pollution and Adverse Birth Outcomes: Effect Modification by Regional Nonvolatile Oxidative Potential

BACKGROUND

Prenatal exposure to fine particulate matter air pollution with aerodynamic diameter ≤2.5 μm (PM_2.5) has been associated with preterm delivery and low birth weight (LBW), but few studies have examined possible effect modification by oxidative potential.

OBJECTIVES

The aim of this study was to evaluate if regional differences in the oxidative potential of PM_2.5 modify the relationship between PM_2.5 and adverse birth outcomes.

METHODS

A retrospective cohort study was conducted using 196,171 singleton births that occurred in 31 cities in the province of Ontario, Canada, from 2006 to 2012. Daily air pollution data were collected from ground monitors, and city-level PM_2.5 oxidative potential was measured. We used random-effects meta-analysis to combine the estimates of effect from regression models across cities on preterm birth, term LBW, and term birth weight and used meta-regression to evaluate the modifying effect of PM_2.5 oxidative potential.

RESULTS

An interquartile increase (2.6 μg/m³) in first-trimester PM_2.5 was positively associated with term LBW among women in the highest quartile of glutathione (GSH)-related oxidative potential [odds ratio (OR)=1.28; 95% confidence interval (CI): 1.10, 1.48], but not the lowest quartile (OR=0.99; 95% CI: 0.87, 1.14; p-interaction=0.03). PM_2.5 on the day of delivery also was associated with preterm birth among women in the highest quartile of GSH-related oxidative potential [hazard ratio (HR)=1.02; 95% CI: 1.01, 1.04], but not the lowest quartile [HR=0.97; 95% CI: 0.95, 1.00; p-interaction=0.04]. Between-city differences in ascorbate (AA)-related oxidative potential did not significantly modify associations with PM_2.5.

CONCLUSIONS

Between-city differences in GSH-related oxidative potential may modify the impact of PM_2.5 on the risk of term LBW and preterm birth. https://doi.org/10.1289/EHP2535.

Ageing at the level of telomeres in association to residential landscape and air pollution at home and work: a review of the current evidence

Studies suggest that leukocyte telomere length is an index of systemic ageing. Here, we discuss telomere length as a marker of biological ageing in relation to residential landscape (greenness), residential air pollution and work-related exposures. Telomere lengths are memories of cumulative oxidative and inflammatory stress, and show to have inverse associations with the risk of non-communicable diseases. For this reason, telomeres are considered as markers of biological ageing. Studies at birth, in children, young adulthood, and elderly show that residential green space, lower traffic exposure and long-term lower exposure to particulate air pollution are associated with longer telomeres. Work-related exposures including exposure to toxic metals, polycyclic aromatic hydrocarbons and particulate matter are associated with shorter telomeres for a given age. In contrast to chronic exposures, evidence is present of the observation that recent exposure is associated with longer telomeres. Our overview shows that the magnitude of residential and work-related environmental factors on telomere length are often as important as many classical lifestyle factors.

Particle Size Distributions of Oxidative Potential of Lung-Deposited Particles: Assessing Contributions from Quinones and Water-Soluble Metals

Redox-active species in ambient particulate matter (PM) cause adverse health effects through the production of reactive oxygen species (ROS) in the human respiratory tract. However, respiratory deposition of these species and their relative contributions to oxidative potential (OP) have not been described. Size-segregated aerosols were collected during haze and nonhaze periods using a micro-orifice uniform deposit impactor sampler at an urban site in Shanghai to address this issue. Samples were analyzed for redox-active species content and PM OP. The average dithiothreitol (DTT) activity of haze samples was approximately 2.4-fold higher than that of nonhaze samples and significantly correlated with quinone and water-soluble metal concentrations. The size-specific distribution data revealed that both water-soluble OP_v^DTT (volume-normalized OP quantified by DTT assay) and OP_m^DTT (mass-normalized OP) were unimodal, peaking at 0.56-1 and 0.1-0.32 μm, respectively, due to contributions from accumulation-mode quinones and water-soluble metals. We further estimated that transition metals (mainly copper and manganese) contributed 55 ± 13% of the DTT activity while quinones accounted for only 8 ± 3%. Multiple-path particle dosimetry calculations estimated that OP deposition in the pulmonary region was mainly from accumulation-mode transition metals despite quinones having the highest DTT activity. This behavior is primarily attributed to the efficiency of deposition of transition metals in the pulmonary region being approximately 1.2-fold greater than that of quinones. These results reveal that accumulation-mode transition metals are significant contributors to the OP of deposited water-soluble particles in the pulmonary region of the lung.

Ambient Air Pollution and Biomarkers of Health Effect

Recently, the air pollution situation of our country is very serious along with the development of urbanization and industrialization. Studies indicate that the exposure of air pollution can cause a rise of incidence and mortality of many diseases, such as chronic obstructive pulmonary disease (COPD), asthma, myocardial infarction, and so on. However, there is now growing evidence showing that significant air pollution exposures are associated with early biomarkers in various systems of the body. In order to better prevent and control the damage effect of air pollution, this article summarizes comprehensively epidemiological studies about the bad effects on the biomarkers of respiratory system, cardiovascular system, and genetic and epigenetic system exposure to ambient air pollution.

Approximation of personal exposure to fine particulate matters (PM2.5) during cooking using solid biomass fuels in the kitchens of rural West Bengal, India

More than 85% of the rural Indian households use traditional solid biofuels (SBFs) for daily cooking. Burning of the easily available unprocessed solid fuels in inefficient earthen cooking stoves produce large quantities of particulate matters. Smaller particulates, especially with aerodynamic diameter of 2.5 μm or less (PM_2.5), largely generated during cooking, are considered to be health damaging in nature. In the present study, kitchen level exposure of women cooks to fine particulate matters during lunch preparation was assessed considering kitchen openness as surrogate to the ventilation condition. Two-way ANCOVA analysis considering meal quantity as a covariate revealed no significant interaction between the openness and the seasons explaining the variability of the personal exposure to the fine particulate matters in rural kitchen during cooking. Multiple linear regression analysis revealed the openness as the only significant predictor for personal exposure to the fine particulate matters. In the present study, the annual average fine particulate matter exposure concentration was found to be 974 μg m^-3.

Residential proximity to major roadways and traffic in relation to outcomes of in vitro fertilization

BACKGROUND

Emerging data from animal and human studies suggest that traffic-related air pollution adversely affects early pregnancy outcomes; however evidence is limited.

OBJECTIVE

We examined whether residential proximity to major roadways and traffic, as proxies for traffic-related air pollution, are associated with in vitro fertilization (IVF) outcomes.

METHODS

This analysis included 423 women enrolled in the Environment and Reproductive Health (EARTH) Study, a prospective cohort study, who underwent 726 IVF cycles (2004-2017). Using geocoded residential addresses collected at study entry, we calculated the distance to nearest major roadway and the traffic density within a 100 m radius. IVF outcomes were abstracted from electronic medical records. We used multivariable generalized linear mixed models to evaluate the associations between residential proximity to major roadways and traffic density and IVF outcomes adjusting for maternal age, body mass index, race, education level, smoking status, and census tract median income.

RESULTS

Closer residential proximity to major roadways was statistically significantly associated with lower probability of implantation and live birth following IVF. The adjusted percentage of IVF cycles resulting in live birth for women living ≥400 m from a major roadway was 46% (95% CI 36, 56%) compared to 33% (95% CI 26, 40%) for women living <50 m (p-for-comparison, 0.04). Of the intermediate outcomes, there were suggestive associations between living closer to major roadways and slightly higher estradiol trigger concentrations (p-trend = 0.16) and lower endometrial thickness (p-trend = 0.06). Near-residence traffic density was not associated with outcomes of IVF.

CONCLUSION

Closer residential proximity to major roadways was related to reduced likelihood of live birth following IVF.

Multi-cellular human bronchial models exposed to diesel exhaust particles: assessment of inflammation, oxidative stress and macrophage polarization

Background

Diesel exhaust particles (DEP) are a major component of outdoor air pollution. DEP mediated pulmonary effects are plausibly linked to inflammatory and oxidative stress response in which macrophages (MQ), epithelial cells and their cell-cell interaction plays a crucial role. Therefore, in this study we aimed at studying the cellular crosstalk between airway epithelial cells with MQ and MQ polarization following exposure to aerosolized DEP by assessing inflammation, oxidative stress, and MQ polarization response markers.

Method

Lung mucosa models including primary bronchial epithelial cells (PBEC) cultured at air-liquid interface (ALI) were co-cultured without (PBEC-ALI) and with MQ (PBEC-ALI/MQ). Cells were exposed to 12.7 μg/cm² aerosolized DEP using XposeALI^®. Control (sham) models were exposed to clean air. Cell viability was assessed. CXCL8 and IL-6 were measured in the basal medium by ELISA. The mRNA expression of inflammatory markers (CXCL8, IL6, TNFα), oxidative stress (NFKB, HMOX1, GPx) and MQ polarization markers (IL10, IL4, IL13, MRC1, MRC2 RETNLA, IL12 andIL23) were measured by qRT-PCR. The surface/mRNA expression of TLR2/TLR4 was detected by FACS and qRT-PCR.

Results

In PBEC-ALI exposure to DEP significantly increased the secretion of CXCL8, mRNA expression of inflammatory markers (CXCL8, TNFα) and oxidative stress markers (NFKB, HMOX1, GPx). However, mRNA expressions of these markers (CXCL8, IL6, NFKB, and HMOX1) were reduced in PBEC-ALI/MQ models after DEP exposure. TLR2 and TLR4 mRNA expression increased after DEP exposure in PBEC-ALI. The surface expression of TLR2 and TLR4 on PBEC was significantly reduced in sham-exposed PBEC-ALI/MQ compared to PBEC-ALI. After DEP exposure surface expression of TLR2 was increased on PBEC of PBEC-ALI/MQ, while TLR4 was decreased in both models. DEP exposure resulted in similar expression pattern of TLR2/TLR4 on MQ as in PBEC. In PBEC-ALI/MQ, DEP exposure increased the mRNA expression of anti-inflammatory M2 macrophage markers (IL10, IL4, IL13, MRC1, MRC2).

Conclusion

The cellular interaction of PBEC with MQ in response to DEP plays a pivotal role for MQ phenotypic alteration towards M2-subtypes, thereby promoting an efficient resolution of the inflammation. Furthermore, this study highlighted the fact that cell–cell interaction using multicellular ALI-models combined with an in vivo-like inhalation exposure system is critical in better mimicking the airway physiology compared with traditional cell culture systems.

Electronic supplementary material

The online version of this article (10.1186/s12989-018-0256-2) contains supplementary material, which is available to authorized users.

Acute effects of PM2.5 on lung function parameters in schoolchildren in Nanjing, China: a panel study

The association between exposure to ambient particulate matter (PM) and reduced lung function parameters has been reported in many works. However, few studies have been conducted in developing countries with high levels of air pollution like China, and little attention has been paid to the acute effects of short-term exposure to air pollution on lung function. The study design consisted of a panel comprising 86 children from the same school in Nanjing, China. Four measurements of lung function were performed. A mixed-effects regression model with study participant as a random effect was used to investigate the relationship between PM_2.5 and lung function. An increase in the current day, 1-day and 2-day moving average PM_2.5 concentration was associated with decreases in lung function indicators. The greatest effect of PM_2.5 on lung function was detected at 1-day moving average PM_2.5 exposure. An increase of 10 μg/m³ in the 1-day moving average PM_2.5 concentration was associated with a 23.22 mL decrease (95% CI: 13.19, 33.25) in Forced Vital Capacity (FVC), a 18.93 mL decrease (95% CI: 9.34, 28.52) in 1-s Forced Expiratory Volume (FEV₁), a 29.38 mL/s decrease (95% CI: -0.40, 59.15) in Peak Expiratory Flow (PEF), and a 27.21 mL/s decrease (95% CI: 8.38, 46.04) in forced expiratory flow 25-75% (FEF_25-75%). The effects of PM_2.5 on lung function had significant lag effects. After an air pollution event, the health effects last for several days and we still need to pay attention to health protection.