Emissions from modern gasoline engines represent an environmental and health risk. In this study, we aimed to compare the toxicity of organic compound mixtures extracted from particulate matter (PM extracts) produced by neat gasoline (E0) and a blend containing 15% ethanol (E15), which is offered as an alternative to non-renewable fossil fuels. Human lung BEAS-2B cells were exposed to PM extracts, and biomarkers of genotoxicity, such as DNA damage evaluated by comet assay, micronuclei formation, levels of phosphorylated histone H2AX, the expression of genes relevant to the DNA damage response, and exposure to polycyclic aromatic hydrocarbons (PAHs), were determined.
View Article and Find Full Text PDFSome metal nanoparticles (NP) are characterized by antimicrobial properties with the potential to be used as alternative antibiotics. However, NP may negatively impact human organism, including mesenchymal stem cells (MSC), a cell population contributing to tissue growth and regeneration. To address these issues, we investigated the toxic effects of selected NP (Ag, ZnO, and CuO) in mouse MSC.
View Article and Find Full Text PDFAir pollution is a dominant environmental exposure factor with significant health consequences. Unexpectedly, research in a heavily polluted region of the Czech Republic, with traditional heavy industry, revealed repeatedly the lowest frequency of micronuclei in the season with the highest concentrations of air pollutants including carcinogenic benzo[a]pyrene (B[a]P). Molecular findings have been collected for more than 10 years from various locations of the Czech Republic, with differing quality of ambient air.
View Article and Find Full Text PDFBackground: To study the impact of oxidative damage associated with particulate matter< 2.5 µm (PM2.5) during prenatal period on the cognitive development in five years old children.
View Article and Find Full Text PDFWe aimed to identify the variables that modify levels of oxidatively damaged DNA and lipid peroxidation in subjects living in diverse localities of the Czech Republic (a rural area, a metropolitan locality, and an industrial region). The sampling of a total of 126 policemen was conducted twice in two sampling seasons. Personal characteristics, concentrations of particulate matter of aerodynamic diameter <2.
View Article and Find Full Text PDFDNA methylation is the most studied epigenetic mechanism that regulates gene expression, and it can serve as a useful biomarker of prior environmental exposure and future health outcomes. This study focused on DNA methylation profiles in a human cohort, comprising 125 nonsmoking city policemen (sampled twice), living and working in three localities (Prague, Ostrava and Ceske Budejovice) of the Czech Republic, who spent the majority of their working time outdoors. The main characterization of the localities, differing by major sources of air pollution, was defined by the stationary air pollution monitoring of PM2.
View Article and Find Full Text PDFThe evaluation of the frequency of micronuclei (MN) is a broadly utilised approach in in vitro toxicity testing. Nevertheless, the specific properties of nanomaterials (NMs) give rise to concerns regarding the optimal methodological variants of the MN assay. In bronchial epithelial cells (BEAS-2B), we tested the genotoxicity of five types of NMs (TiO: NM101, NM103; SiO: NM200; Ag: NM300K, NM302) using four variants of MN protocols, differing in the time of exposure and the application of cytochalasin-B combined with the simultaneous and delayed co-treatment with NMs.
View Article and Find Full Text PDFThe toxicities of many environmental polycyclic aromatic hydrocarbons (PAHs), in particular those of high-molecular-weight PAHs (with MW higher than 300), remain poorly characterized. The objective of this study was to evaluate the ability of selected environmentally relevant PAHs with MW 302 (MW302 PAHs) to activate the aryl hydrocarbon receptor (AhR), since this represents a major toxic mode of action of PAHs. A large number of the evaluated compounds exhibited strong AhR-mediated activities, in particular in human models.
View Article and Find Full Text PDFThe aryl hydrocarbon receptor (AhR) transcription factor is activated by polycyclic aromatic hydrocarbons (PAH) and other ligands. Activated AhR binds to dioxin responsive elements (DRE) and initiates transcription of target genes, including the gene encoding prostaglandin endoperoxide synthase 2 (PTGS-2), which is also activated by the transcription factor NF-ĸB. PTGS-2 catalyzes the conversion of arachidonic acid (AA) into prostaglandins, thromboxanes or isoprostanes.
View Article and Find Full Text PDFWe investigated the transcriptomic response and epigenetic changes in the lungs of mice exposed to inhalation of copper(II) oxide nanoparticles (CuO NPs) (8 × 10 NPs/m) for periods of 3 days, 2 weeks, 6 weeks, and 3 months. A whole genome transcriptome and miRNA analysis was performed using next generation sequencing. Global DNA methylation was assessed by ELISA.
View Article and Find Full Text PDFMutat Res Genet Toxicol Environ Mutagen
September 2019
An analysis of the toxic effects of emissions should reflect real traffic conditions. The exhaust emissions of particulate matter from diesel engines strongly depend on their operating conditions, with low-speed, low-load "urban creep" conditions, common for truck traffic in heavily congested urban areas, being one of the worst. We aimed to detect the genotoxicity of organic extracts from particulate matter in the exhaust of the diesel engine Zetor 1505 running on diesel and biodiesel (B100) fuels at characteristic modes of extended "urban creep", typical for transit truck traffic in Prague, comparing the first 5 min of idling with extended (20-80 min) idling, full load after idle, "stabilized" full load, and 30% load.
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) may cause lipid peroxidation via reactive oxygen species generation. 15-F2t-isoprostane (IsoP), an oxidative stress marker, is formed from arachidonic acid (AA) by a free-radical induced oxidation. AA may also be converted to prostaglandins (PG) by prostaglandin-endoperoxide synthase (PTGS) induced by NF-κB.
View Article and Find Full Text PDFDietary carcinogens, such as benzo[a]pyrene (BaP), are suspected to contribute to colorectal cancer development. n-3 Polyunsaturated fatty acids (PUFAs) decrease colorectal cancer risk in individuals consuming diets rich in PUFAs. Here, we investigated the impact of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid on metabolism and genotoxicity of BaP in human cell models derived from the colon: HT-29 and HCT-116 cell lines.
View Article and Find Full Text PDFPrenatal exposure to air pollution is associated with intrauterine growth restriction and low birth weight. Gene expression changes in newborns in relation to air pollution have not been sufficiently studied. We analyzed whole genome expression in cord blood leukocytes of 202 newborns from diverse localities of the Czech Republic, differing among other factors in levels of air pollution: the district of Karvina (characterized by higher concentration of air pollutants) and Ceske Budejovice (lower air pollution levels).
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) associated with particulate matter (PM) may induce oxidative damage via reactive oxygen species (ROS) generation. However, the kinetics of ROS production and the link with antioxidant response induction has not been well studied. To elucidate the differences in oxidative potential of individual PAH compounds and extractable organic matter (EOM) from PM containing various PAH mixtures, we studied ROS formation and antioxidant response [total antioxidant capacity (TAC) and expression of HMOX1 and TXNRD1] in human alveolar basal epithelial cells (A549 cells) and human embryonic lung fibroblasts (HEL12469 cells).
View Article and Find Full Text PDFObjectives: The aim of our study is to investigate the impact of the type of delivery - vaginal vs. cesarean section on oxidative damage determined as the lipid peroxidation (15-F2t-isoprostane (15-F2t-IsoP) in the cord blood of newborns and venous blood from mothers in two localities with different levels of air pollution: Ceske Budejovice (CB), a locality with a clean air, and Karvina, a locality with high air pollution.
Resutls: In Karvina, the concentration of PM2.
The Northern Moravia Region is the most polluted region in the Czech Republic by particulate matter (PM) and carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) as benzo[a]pyrene (B[a]P) by heavy industry and local heating. This specific situation was used to study the impact of air pollution on newborns in the exposed Karviná district and control district of České Budějovice. Biological material from newborns and mothers was collected in summer and winter seasons.
View Article and Find Full Text PDFButyrate, a short-chain fatty acid produced by fermentation of dietary fiber, is an important regulator of colonic epithelium homeostasis. In this study, we investigated the impact of this histone deacetylase (HDAC) inhibitor on expression/activity of cytochrome P450 family 1 (CYP1) and on metabolism of carcinogenic polycyclic aromatic hydrocarbon, benzo[a]pyrene (BaP), in colon epithelial cells. Sodium butyrate (NaBt) strongly potentiated the BaP-induced expression of CYP1A1 in human colon carcinoma HCT116 cells.
View Article and Find Full Text PDFWe investigated the toxicity of benzo[a]pyrene (B[a]P), 1-nitropyrene (1-NP) and 3-nitrobenzanthrone (3-NBA) in A549 cells. Cells were treated for 4 h and 24 h with: B[a]P (0.1 and 1 μM), 1-NP (1 and 10 μM) and 3-NBA (0.
View Article and Find Full Text PDFAmbient air particulate matter (PM) represents a class of heterogeneous substances that form one component of air pollution. Oxidative stress has been implicated as an important action mechanism for PM on the human organism. Oxidative damage induced by reactive oxygen species (ROS) may affect any cellular macromolecule.
View Article and Find Full Text PDFThis study quantified the temporal variability of concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs), genotoxicity, oxidative DNA damage and dioxin-like activity of the extractable organic matter (EOM) of atmospheric aerosol particles of aerodynamic diameter (dae, μm) coarse (1 < dae < 10), upper- (0.5 < dae < 1) and lower-accumulation (0.17 < dae < 0.
View Article and Find Full Text PDFDeregulation of Wnt/β-catenin signalling plays an important role in the pathogenesis of colorectal cancer. Interestingly, this pathway has been recently implicated in transcriptional control of cytochrome P450 (CYP) family 1 enzymes, which are responsible for bioactivation of a number of dietary carcinogens. In the present study, we investigated the impact of inhibition of Wnt/β-catenin pathway on metabolism and genotoxicity of benzo[a]pyrene (BaP), a highly mutagenic polycyclic aromatic hydrocarbon and an efficient ligand of the aryl hydrocarbon receptor, which is known as a primary regulator of CYP1 expression, in cellular models derived from colorectal tumours.
View Article and Find Full Text PDFDiesel exhaust particles (DEP) and the associated complex mixtures of organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), or their derivatives, have been suggested to exert deleterious effects on human health. We used a set of defined cellular models representing liver, lung and prostate tissues, in order to compare non-genotoxic and genotoxic effects of crude and fractionated extract of a standard reference DEP material - SRM 1650b. We focused on the aryl hydrocarbon receptor (AhR)-mediated activity, modulation of cell proliferation, formation of DNA adducts, oxidative DNA damage, and induction of DNA damage responses, including evaluation of apoptosis, and phosphorylation of p53 tumor suppressor and checkpoint kinases (Chk).
View Article and Find Full Text PDFIn this study, we compared the genotoxicity and aryl hydrocarbon receptor (AhR)-dependent transcriptional changes of selected target genes in human lung epithelial A549 cells incubated for 24 h, either with extractable organic matter (EOMs) from airborne particles <2.5 μm (PM2.5) collected at four localities from heavily polluted areas of the Czech Republic or two representative toxic polycyclic aromatic hydrocarbons (PAHs) present in EOMs, benzo[a]pyrene (B[a]P) and benzo[k]fluoranthene (B[k]F).
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