Exposure to air pollution is associated with neurological diseases. Traffic is a major source of air pollution, consisting of a complex mixture of ultrafine particles, that can invade the brain and induce a microglia-mediated inflammatory response. However, the exact mechanisms of how traffic-related particles impact human microglia remain poorly understood. This study investigates the effects of diesel exhaust particles (DEPs) on human induced pluripotent stem cell-derived microglia-like cells (iMGL). We exposed iMGLs to three different DEPs and studied the impact on the iMGL transcriptome and functionality, focusing on cytokine secretion, mitochondrial respiration, lysosomal function, and phagocytosis. A20 particles were collected from a heavy-duty engine run with petroleum diesel. For A0, the same engine was run with renewable diesel. E6 was produced with a modern 2019 model diesel passenger car run with renewable diesel. RNAseq revealed activation of the cytokine storm pathway and inhibition of the autophagy pathway in iMGLs after exposure to particles derived from older diesel emission technology (A20, A0). Particles from the modern diesel engine technology (E6) did not alter microglial transcriptome after 24 h exposure. A20 and A0 exposure led to impaired lysosomal functions in iMGLs. In contrast, E6 did not cause major alterations in microglia functions. In addition, we show that response to particles is more pronounced in human iMGLs compared to mouse primary microglia. To conclude, particles from older emission technology impair phago-lysosomal functions of iMGLs, but modern alternatives with filtration do not induce drastic changes in the functionality of iMGLs.

• Klíčová slova
• Air pollution, Diesel, Human microglia, Lysosome, iPSC,
• MeSH
• indukované pluripotentní kmenové buňky MeSH
• látky znečišťující vzduch * toxicita   MeSH
• lidé MeSH
• lyzozomy * účinky léků   MeSH
• mikroglie * účinky léků   MeSH
• pevné částice * toxicita   MeSH
• výfukové emise vozidel * toxicita   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice * MeSH
• výfukové emise vozidel * MeSH

Traffic-related ultrafine particles (UFPs) are an emerging health concern affecting the brain and increasing the risk of Alzheimer's disease (AD). PI3K/AKT signaling is known to contribute to neuronal survival and to be altered in AD. The nasal olfactory mucosa (OM) is a sensory tissue exposed directly to ambient air, and a starting point for olfactory neural circuits towards the brain. Evidence of air pollution-induced transcriptional regulation via microRNAs (miRNA) and DNA methylation (DNAmet) is accumulating and air pollutant-mediated disturbances in PI3K/AKT signaling have been reported. By utilizing a highly translational human-based in vitro model of OM, we aimed to investigate possible gene regulatory mechanisms in PI3K/AKT signaling induced by UFPs, and to compare the responses between cognitively healthy and individuals with AD. miRNA expression was analyzed using next-generation sequencing (NGS) and chip-based methylation analysis was performed to detect differentially methylated loci (DML). These data were combined with previously published transcriptomics analysis (mRNA) to construct an mRNA-miRNA-DNAmet-integrative network. Protein level changes were studied by immunoassays. We observed UFP-induced reductions in viability and increases in oxidative stress and DNA damage without eminent cell death. Integrative network analysis revealed multiple connections of miRNAs to differentially expressed genes in the PI3K/AKT pathway, and effects were most prominent in AD cells. Similarly, in AD cells DML were identified in transcription factor and apoptosis genes, downstream of PI3K/AKT signaling. Conclusively, traffic-related UFPs influence gene regulation of PI3K/AKT signaling to modulate OM cell survival, with existing AD pathology resulting in heightened vulnerability to UFP effects.

• Klíčová slova
• Alzheimer’s disease (AD), DNA methylation (DNAmet), integrative mRNA-miRNA-DNAmet analysis, MicroRNA (miRNA), Olfactory mucosa (OM), PI3K/AKT signaling, Ultrafine particle (UFP),
• MeSH
• Alzheimerova nemoc MeSH
• čichová sliznice * účinky léků   metabolismus   cytologie   MeSH
• fosfatidylinositol-3-kinasy metabolismus   MeSH
• látky znečišťující vzduch * toxicita   MeSH
• lidé MeSH
• metylace DNA MeSH
• mikro RNA metabolismus   MeSH
• pevné částice * toxicita   MeSH
• protoonkogenní proteiny c-akt metabolismus   MeSH
• regulace genové exprese * účinky léků   MeSH
• signální transdukce účinky léků   MeSH
• výfukové emise vozidel * toxicita   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfatidylinositol-3-kinasy MeSH
• látky znečišťující vzduch * MeSH
• mikro RNA MeSH
• pevné částice * MeSH
• protoonkogenní proteiny c-akt MeSH
• výfukové emise vozidel * MeSH

We developed a mobile laboratory allowing field exposure of lung tissue models to ambient air at localities with various pollution sources (Background, Industrial, Traffic, Urban) in different seasons (summer/fall/winter). In samples originating from healthy and asthmatic individuals, we assessed the parameters of toxicity, lipid peroxidation and immune response; we further performed comprehensive monitoring of air pollutants at sampling sites. We measured lactate dehydrogenase (LDH) and adenylate kinase (AK) production and transepithelial electrical resistance (TEER), analyzed 15-F2t-isopostane (IsoP) and a panel of 20 cytokines/chemokines/growth factors. In the ambient air, we detected particulate matter (PM), and other relevant chemicals (benzene, benzo[a]pyrene (BaP), NOx). In the Traffic locality, we found very high concentrations of ultrafine particles and NOx and observed low TEER values in the exposed samples, indicating significant traffic-related toxicity of the ambient air. In the Urban locality, sampled in winter, we observed high PM and BaP levels. We found lower AK levels in samples from healthy individuals exposed in this locality than in the asthmatic samples. In the samples from the Industrial locality, sampled in summer, we detected higher concentrations of TNFα, MIP-1α, Eotaxin, GROα, GM-CSF, IL-6 and IL-7 than in the Urban locality samples. We hypothesize that pollen or other plant-related components of the ambient air were responsible for this response. In conclusion, our data proved the feasibility of our mobile laboratory for field measurements of the biological response of lung tissue models exposed to ambient air, reflecting not only the levels of toxic compounds, but also season-specific parameters.

• Klíčová slova
• air-liquid interface, asthma, lung tissue model, outdoor air pollution, real-world exposure,
• MeSH
• bronchiální astma * metabolismus   MeSH
• cytokiny metabolismus   MeSH
• dospělí MeSH
• látky znečišťující vzduch * toxicita   analýza   MeSH
• lidé MeSH
• monitorování životního prostředí * metody   MeSH
• pevné částice analýza   toxicita   MeSH
• respirační sliznice * účinky léků   metabolismus   MeSH
• roční období MeSH
• vystavení vlivu životního prostředí * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• cytokiny MeSH
• látky znečišťující vzduch * MeSH
• pevné částice MeSH

Persons living in industrial environments are exposed to levels of air pollution that can affect their health and fertility. The Czech capital city, Prague, and the Ostrava industrial agglomeration differ in their major sources of air pollution. In Prague, heavy traffic produces high levels of nitrogen oxides throughout the year. In the Ostrava region, an iron industry and local heating are sources of particulate matter (PM) and benzo[a]pyrene (B[a]P), especially in the winter. We evaluated the effects of air pollution on human sperm mitochondrial DNA (mtDNA). Using real-time PCR, we analysed sperm mtDNA copy number and deletion rate in Prague city policemen in two seasons (spring and autumn) and compared the results with those from Ostrava. In Prague, the sperm mtDNA deletion rate was significantly higher in autumn than in spring, which is the opposite of the results from Ostrava. The sperm mtDNA copy number did not show any seasonal differences in either of the cities; it was correlated negatively with sperm concentration, motility, and viability, and with sperm chromatin integrity (assessed with the Sperm Chromatin Structure Assay). The comparison between the two cities showed that the sperm mtDNA deletion rate in spring and the sperm mtDNA copy number in autumn were significantly lower in Prague vs. Ostrava. Our study supports the hypothesis that sperm mtDNA deletion rate is affected by the composition of air pollution. Sperm mtDNA abundance is closely associated with chromatin damage and standard semen characteristics.

• Klíčová slova
• Exposure, Industry, MtDNA, Policemen, Semen, Traffic,
• MeSH
• dospělí MeSH
• látky znečišťující vzduch toxicita   škodlivé účinky   MeSH
• lidé MeSH
• mitochondriální DNA * genetika   MeSH
• motilita spermií účinky léků   MeSH
• pevné částice toxicita   škodlivé účinky   MeSH
• policie MeSH
• roční období MeSH
• spermie * účinky léků   MeSH
• variabilita počtu kopií segmentů DNA * MeSH
• znečištění ovzduší * škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• látky znečišťující vzduch MeSH
• mitochondriální DNA * MeSH
• pevné částice MeSH

Environmental exposure is associated with increased incidence of respiratory and cardiovascular diseases and reduced fertility. Exposure to air pollution can influence gene expression through epigenetic mechanisms. In this study, we analysed gene-specific CpG methylation in spermatozoa of city policemen occupationally exposed to air pollution in two Czech cities differing by sources and composition of the air pollution. In Prague, the pollution is mainly formed by NO2 from heavy traffic. Ostrava is a hotspot of industrial air pollution with high concentrations of particular matter (PM) and benzo[a]pyrene (B[a]P). We performed genome-wide methylation sequencing using the SureSelectXT Human Methyl-Seq system (Agilent Technologies) and next-generation sequencing to reveal differentially methylated CpG sites and regions. We identified differential methylation in the region chr5:662169 - 663376 annotated to genes CEP72 and TPPP. The region was then analysed in sperm DNA from 117 policemen using targeted methylation sequencing, which proved its hypermethylation in sperm of Ostrava policemen.

• Klíčová slova
• Air pollution, DNA methylation, spermatozoa,
• MeSH
• dospělí MeSH
• látky znečišťující vzduch * analýza   toxicita   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metylace DNA * účinky léků   MeSH
• pevné částice analýza   toxicita   MeSH
• policie MeSH
• pracovní expozice MeSH
• spermie * účinky léků   MeSH
• znečištění ovzduší * škodlivé účinky   analýza   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH

Constituents of air pollution, the ultrafine particles (UFP) with a diameter of ≤0.1 μm, are considerably related to traffic emissions. Several studies link air pollution to Alzheimer's disease (AD), yet the exact relationship between the two remains poorly understood. Mitochondria are known targets of environmental toxicants, and their dysfunction is associated with neurodegenerative diseases. The olfactory mucosa (OM), located at the rooftop of the nasal cavity, is directly exposed to the environment and in contact with the brain. Mounting evidence suggests that the UFPs can impact the brain directly through the olfactory tract. By using primary human OM cultures established from nasal biopsies of cognitively healthy controls and individuals diagnosed with AD, we aimed to decipher the effects of traffic-related UFPs on mitochondria. The UFP samples were collected from the exhausts of a modern heavy-duty diesel engine (HDE) without aftertreatment systems, run with renewable diesel (A0) and petroleum diesel (A20), and from an engine of a 2019 model diesel passenger car (DI-E6d) equipped with state-of-the-art aftertreatment devices and run with renewable diesel (Euro6). OM cells were exposed to three different UFPs for 24-h and 72-h, after which cellular processes were assessed on the functional and transcriptomic levels. Our results show that UFPs impair mitochondrial functions in primary human OM cells by hampering oxidative phosphorylation (OXPHOS) and redox balance, and the responses of AD cells differ from cognitively healthy controls. RNA-Seq and IPA® revealed inhibition of OXPHOS and mitochondrial dysfunction in response to UFPs A0 and A20. Functional validation confirmed that A0 and A20 impair cellular respiration, decrease ATP levels, and disturb redox balance by altering NAD and glutathione metabolism, leading to increased ROS and oxidative stress. RNA-Seq and functional assessment revealed the presence of AD-related alterations in human OM cells and that different fuels and engine technologies elicit differential effects.

• Klíčová slova
• Mitochondrial dysfunction, Olfactory mucosa (OM), Oxidative phosphorylation (OXPHOS), RNA sequencing (RNA-Seq), Redox balance, Ultrafine particles (UFP),
• MeSH
• Alzheimerova nemoc * metabolismus   etiologie   patologie   chemicky indukované   MeSH
• čichová sliznice * metabolismus   patologie   účinky léků   MeSH
• látky znečišťující vzduch toxicita   škodlivé účinky   MeSH
• lidé MeSH
• mitochondrie * metabolismus   účinky léků   MeSH
• oxidační stres účinky léků   MeSH
• pevné částice * škodlivé účinky   toxicita   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• senioři MeSH
• výfukové emise vozidel toxicita   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• látky znečišťující vzduch MeSH
• pevné částice * MeSH
• reaktivní formy kyslíku MeSH
• výfukové emise vozidel MeSH

Ultrafine particles (UFP) with a diameter of ≤0.1 μm, are contributors to ambient air pollution and derived mainly from traffic emissions, yet their health effects remain poorly characterized. The olfactory mucosa (OM) is located at the rooftop of the nasal cavity and directly exposed to both the environment and the brain. Mounting evidence suggests that pollutant particles affect the brain through the olfactory tract, however, the exact cellular mechanisms of how the OM responds to air pollutants remain poorly known. Here we show that the responses of primary human OM cells are altered upon exposure to UFPs and that different fuels and engines elicit different adverse effects. We used UFPs collected from exhausts of a heavy-duty-engine run with renewable diesel (A0) and fossil diesel (A20), and from a modern diesel vehicle run with renewable diesel (Euro6) and compared their health effects on the OM cells by assessing cellular processes on the functional and transcriptomic levels. Quantification revealed all samples as UFPs with the majority of particles being ≤0.1 μm by an aerodynamic diameter. Exposure to A0 and A20 induced substantial alterations in processes associated with inflammatory response, xenobiotic metabolism, olfactory signaling, and epithelial integrity. Euro6 caused only negligible changes, demonstrating the efficacy of aftertreatment devices. Furthermore, when compared to A20, A0 elicited less pronounced effects on OM cells, suggesting renewable diesel induces less adverse effects in OM cells. Prior studies and these results suggest that PAHs may disturb the inflammatory process and xenobiotic metabolism in the OM and that UFPs might mediate harmful effects on the brain through the olfactory route. This study provides important information on the adverse effects of UFPs in a human-based in vitro model, therefore providing new insight to form the basis for mitigation and preventive actions against the possible toxicological impairments caused by UFP exposure.

• Klíčová slova
• Air pollution, RNA-Seq, Traffic emissions, Ultrafine particles (UFP),
• MeSH
• čichová sliznice chemie   MeSH
• látky znečišťující vzduch * toxicita   analýza   MeSH
• lidé MeSH
• pevné částice toxicita   analýza   MeSH
• výfukové emise vozidel toxicita   analýza   MeSH
• xenobiotika * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH
• výfukové emise vozidel MeSH
• xenobiotika * MeSH

This study evaluated how exposure to the ubiquitous air pollution component, ultrafine particles (UFPs), alters the olfactory bulb (OB) transcriptome. The study utilised a whole-body inhalation chamber to simulate real-life conditions and focused on UFPs due to their high translocation and deposition ability in OBs as well as their prevalence in ambient air. Female C57BL/6J mice were exposed to clean air or to freshly generated combustion derived UFPs for two weeks, after which OBs were dissected and mRNA transcripts were investigated using RNA sequencing analysis. For the first time, transcriptomics was applied to determine changes in mRNA expression levels occurring after subacute exposure to UFPs in the OBs. We found forty-five newly described mRNAs to be involved in air pollution-induced responses, including genes involved in odorant binding, synaptic regulation, and myelination signalling pathway, providing new gene candidates for future research. This study provides new insights for the environmental science and neuroscience fields and nominates future research directions.

• Klíčová slova
• Air pollution, Brain, Myelin protein zero (Mpz), Odorant-binding protein (OBP), Olfactory bulb, Ultrafine particles (UFP),
• MeSH
• biologické markery metabolismus   MeSH
• bulbus olfactorius chemie   metabolismus   MeSH
• látky znečišťující vzduch * toxicita   analýza   MeSH
• messenger RNA metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• pevné částice toxicita   analýza   MeSH
• stanovení celkové genové exprese MeSH
• transkriptom MeSH
• velikost částic MeSH
• znečištění ovzduší * analýza   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biologické markery MeSH
• látky znečišťující vzduch * MeSH
• messenger RNA MeSH
• pevné částice MeSH

Air pollution is the leading cause of lung cancer after tobacco smoking, contributing to 20% of all lung cancer deaths. Increased risk associated with living near trafficked roads, occupational exposure to diesel exhaust, indoor coal combustion and cigarette smoking, suggest that combustion components in ambient fine particulate matter (PM2.5), such as polycyclic aromatic hydrocarbons (PAHs), may be central drivers of lung cancer. Activation of the aryl hydrocarbon receptor (AhR) induces expression of xenobiotic-metabolizing enzymes (XMEs) and increase PAH metabolism, formation of reactive metabolites, oxidative stress, DNA damage and mutagenesis. Lung cancer tissues from smokers and workers exposed to high combustion PM levels contain mutagenic signatures derived from PAHs. However, recent findings suggest that ambient air PM2.5 exposure primarily induces lung cancer development through tumor promotion of cells harboring naturally acquired oncogenic mutations, thus lacking typical PAH-induced mutations. On this background, we discuss the role of AhR and PAHs in lung cancer development caused by air pollution focusing on the tumor promoting properties including metabolism, immune system, cell proliferation and survival, tumor microenvironment, cell-to-cell communication, tumor growth and metastasis. We suggest that the dichotomy in lung cancer patterns observed between smoking and outdoor air PM2.5 represent the two ends of a dose-response continuum of combustion PM exposure, where tumor promotion in the peripheral lung appears to be the driving factor at the relatively low-dose exposures from ambient air PM2.5, whereas genotoxicity in the central airways becomes increasingly more important at the higher combustion PM levels encountered through smoking and occupational exposure.

• Klíčová slova
• Air pollution, Carcinogenesis, Diesel exhaust, Genotoxicity, Inflammation, Occupational exposure, Smoking, Tumor metastasis, Tumor microenvironment, Tumor promotion,
• MeSH
• látky znečišťující vzduch * toxicita   MeSH
• lidé MeSH
• monitorování životního prostředí MeSH
• nádorové mikroprostředí MeSH
• nádory plic * chemicky indukované   genetika   MeSH
• pevné částice toxicita   MeSH
• polycyklické aromatické uhlovodíky * toxicita   MeSH
• receptory aromatických uhlovodíků genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH
• polycyklické aromatické uhlovodíky * MeSH
• receptory aromatických uhlovodíků MeSH

The aims were to characterize the content of elements and polycyclic aromatic hydrocarbons (PAHs) in size-separated particulate matter (PM) sampled in a road tunnel, estimate the contribution of PAHs to the toxic potential, and measure the pro-inflammatory potential of PM samples and extracts with increasing polarity. Several elements/metals previously associated with cytokine responses were found. Based on PAHs levels and published PAHs potency, the calculated mutagenic and carcinogenic activities of size-separated samples were somewhat lower for coarse than fine and ultrafine PM. The AhR-activity of the corresponding PM extracts measured in an AhR-luciferase reporter model (human hepatocytes) were more similar. The highest AhR-activity was found in the neutral (parent and alkylated PAHs) and polar (oxy-PAHs) fractions, while the semi-polar fractions (mono-nitrated-PAHs) had only weak activity. The neutral and polar aromatic fractions from coarse and fine PM were also found to induce higher pro-inflammatory responses and CYP1A1 expression in human bronchial epithelial cells (HBEC3-KT) than the semi-polar fractions. Fine PM induced higher pro-inflammatory responses than coarse PM. AhR-inhibition reduced cytokine responses induced by parent PM and extracts of both size fractions. Contributors to the toxic potentials include PAHs and oxy-PAHs, but substantial contributions from other organic compounds and/or metals are likely.

• Klíčová slova
• Air pollution, Airway epithelial cells, Aryl hydrocarbon receptor (AhR), Diesel exhaust particles, Inflammation, Metals, Polyaromatic compounds,
• MeSH
• cytokiny MeSH
• epitelové buňky MeSH
• hepatocyty MeSH
• látky znečišťující vzduch * toxicita   analýza   MeSH
• lidé MeSH
• organické látky MeSH
• pevné částice toxicita   analýza   MeSH
• polycyklické aromatické uhlovodíky * toxicita   analýza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokiny MeSH
• látky znečišťující vzduch * MeSH
• organické látky MeSH
• pevné částice MeSH
• polycyklické aromatické uhlovodíky * MeSH