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1.
Part Fibre Toxicol ; 21(1): 38, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300536

RESUMO

BACKGROUND: The formation of secondary organic aerosols (SOA) by atmospheric oxidation reactions substantially contributes to the burden of fine particulate matter (PM2.5), which has been associated with adverse health effects (e.g., cardiovascular diseases). However, the molecular and cellular effects of atmospheric aging on aerosol toxicity have not been fully elucidated, especially in model systems that enable cell-to-cell signaling. METHODS: In this study, we aimed to elucidate the complexity of atmospheric aerosol toxicology by exposing a coculture model system consisting of an alveolar (A549) and an endothelial (EA.hy926) cell line seeded in a 3D orientation at the air‒liquid interface for 4 h to model aerosols. Simulation of atmospheric aging was performed on volatile biogenic (ß-pinene) or anthropogenic (naphthalene) precursors of SOA condensing on soot particles. The similar physical properties for both SOA, but distinct differences in chemical composition (e.g., aromatic compounds, oxidation state, unsaturated carbonyls) enabled to determine specifically induced toxic effects of SOA. RESULTS: In A549 cells, exposure to naphthalene-derived SOA induced stress-related airway remodeling and an early type I immune response to a greater extent. Transcriptomic analysis of EA.hy926 cells not directly exposed to aerosol and integration with metabolome data indicated generalized systemic effects resulting from the activation of early response genes and the involvement of cardiovascular disease (CVD) -related pathways, such as the intracellular signal transduction pathway (PI3K/AKT) and pathways associated with endothelial dysfunction (iNOS; PDGF). Greater induction following anthropogenic SOA exposure might be causative for the observed secondary genotoxicity. CONCLUSION: Our findings revealed that the specific effects of SOA on directly exposed epithelial cells are highly dependent on the chemical identity, whereas non directly exposed endothelial cells exhibit more generalized systemic effects with the activation of early stress response genes and the involvement of CVD-related pathways. However, a greater correlation was made between the exposure to the anthropogenic SOA compared to the biogenic SOA. In summary, our study highlights the importance of chemical aerosol composition and the use of cell systems with cell-to-cell interplay on toxicological outcomes.


Assuntos
Aerossóis , Técnicas de Cocultura , Células Epiteliais , Material Particulado , Transdução de Sinais , Transcriptoma , Humanos , Material Particulado/toxicidade , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células A549 , Poluentes Atmosféricos/toxicidade , Metabolômica , Metaboloma/efeitos dos fármacos
2.
J Appl Toxicol ; 43(8): 1225-1241, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36869434

RESUMO

The prevalence of allergic diseases is constantly increasing since few decades. Anthropogenic ultrafine particles (UFPs) and allergenic aerosols is highly involved in this increase; however, the underlying cellular mechanisms are not yet understood. Studies observing these effects focused mainly on singular in vivo or in vitro exposures of single particle sources, while there is only limited evidence on their subsequent or combined effects. Our study aimed at evaluating the effect of subsequent exposures to allergy-related anthropogenic and biogenic aerosols on cellular mechanism exposed at air-liquid interface (ALI) conditions. Bronchial epithelial BEAS-2B cells were exposed to UFP-rich combustion aerosols for 2 h with or without allergen pre-exposure to birch pollen extract (BPE) or house dust mite extract (HDME). The physicochemical properties of the generated particles were characterized by state-of-the-art analytical instrumentation. We evaluated the cellular response in terms of cytotoxicity, oxidative stress, genotoxicity, and in-depth gene expression profiling. We observed that single exposures with UFP, BPE, and HDME cause genotoxicity. Exposure to UFP induced pro-inflammatory canonical pathways, shifting to a more xenobiotic-related response with longer preincubation time. With additional allergen exposure, the modulation of pro-inflammatory and xenobiotic signaling was more pronounced and appeared faster. Moreover, aryl hydrocarbon receptor (AhR) signaling activation showed to be an important feature of UFP toxicity, which was especially pronounced upon pre-exposure. In summary, we were able to demonstrate the importance of subsequent exposure studies to understand realistic exposure situations and to identify possible adjuvant allergic effects and the underlying molecular mechanisms.


Assuntos
Poluentes Atmosféricos , Hipersensibilidade , Humanos , Material Particulado/análise , Poluentes Atmosféricos/química , Alérgenos/toxicidade , Xenobióticos , Células Epiteliais/metabolismo , Aerossóis/toxicidade , Tamanho da Partícula
3.
Environ Res ; 211: 112968, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35240115

RESUMO

Pollen related allergic diseases have been increasing for decades. The reasons for this increase are unknown, but environmental pollution like diesel exhaust seem to play a role. While previous studies explored the effects of pollen extracts, we studied here for the first time priming effects of diesel exhaust on native pollen exposure using a novel experimental setup. METHODS: Human bronchial epithelial BEAS-2B cells were exposed to native birch pollen (real life intact pollen, not pollen extracts) at the air-liquid interface (pollen-ALI). BEAS-2B cells were also pre-exposed in a diesel-ALI to diesel CAST for 2 h (a model for diesel exhaust) and then to pollen in the pollen-ALI 24 h later. Effects were analysed by genome wide transcriptome analysis after 2 h 25 min, 6 h 50 min and 24 h. Selected genes were confirmed by qRT-PCR. RESULTS: Bronchial epithelial cells exposed to native pollen showed the highest transcriptomic changes after about 24 h. About 3157 genes were significantly up- or down-regulated for all time points combined. After pre-exposure to diesel exhaust the maximum reaction to pollen had shifted to about 2.5 h after exposure, plus the reaction to pollen was desensitised as only 560 genes were differentially regulated. Only 97 genes were affected synergistically. Of these, enrichment analysis showed that genes involved in immune and inflammatory response were involved. CONCLUSION: Diesel exhaust seems to prime cells to react more rapidly to native pollen exposure, especially inflammation related genes, a factor known to facilitate the development of allergic sensitization. The marker genes here detected could guide studies in humans when investigating whether modern and outdoor diesel exhaust exposure is still detrimental for the development of allergic disease.


Assuntos
Pólen , Emissões de Veículos , Células Epiteliais , Humanos , Inflamação , Extratos Vegetais/farmacologia , Emissões de Veículos/toxicidade
4.
Environ Res ; 179(Pt A): 108798, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31629947

RESUMO

BACKGROUND: Volcanic plumes are complex environments composed of gases and ash particles, where chemical and physical processes occur at different temperature and compositional regimes. Commonly, soluble sulphate- and chloride-bearing salts are formed on ash as gases interact with ash surfaces. Exposure to respirable volcanic ash following an eruption is potentially a significant health concern. The impact of such gas-ash interactions on ash toxicity is wholly un-investigated. Here, we study, for the first time, whether the interaction of volcanic particles with sulphur dioxide (SO2) gas, and the resulting presence of sulphate salt deposits on particle surfaces, influences toxicity to the respiratory system, using an advanced in vitro approach. METHODS: To emplace surface sulphate salts on particles, via replication of the physicochemical reactions that occur between pristine ash surfaces and volcanic gas, analogue substrates (powdered synthetic volcanic glass and natural pumice) were exposed to SO2 at 500 °C, in a novel Advanced Gas-Ash Reactor, resulting in salt-laden particles. The solubility of surface salt deposits was then assessed by leaching in water and geochemical modelling. A human multicellular lung model was exposed to aerosolised salt-laden and pristine (salt-free) particles, and incubated for 24 h. Cell cultures were subsequently assessed for biological endpoints, including cytotoxicity (lactate dehydrogenase release), oxidative stress (oxidative stress-related gene expression; heme oxygenase 1 and NAD(P)H dehydrogenase [quinone] 1) and its (pro-)inflammatory response (tumour necrosis factor α, interleukin 8 and interleukin 1ß at gene and protein levels). RESULTS: In the lung cell model no significant effects were observed between the pristine and SO2-exposed particles, indicating that the surface salt deposits, and the underlying alterations to the substrate, do not cause acute adverse effects in vitro. Based on the leachate data, the majority of the sulphate salts from the ash surfaces are likely to dissolve in the lungs prior to cellular uptake. CONCLUSIONS: The findings of this study indicate that interaction of volcanic ash with SO2 during ash generation and transport does not significantly affect the respiratory toxicity of volcanic ash in vitro. Therefore, sulphate salts are unlikely a dominant factor controlling variability in in vitro toxicity assessments observed during previous eruption response efforts.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Dióxido de Enxofre , Erupções Vulcânicas , Humanos , Pulmão , Estresse Oxidativo
5.
Inhal Toxicol ; 30(1): 40-48, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29508652

RESUMO

Ambient air pollutant levels vary widely in space and time, therefore thorough local evaluation of possible effects is needed. In vitro approaches using lung cell cultures grown at the air-liquid interface and directly exposed to ambient air can offer a reliable addition to animal experimentations and epidemiological studies. To evaluate the adverse effects of ambient air in summer and winter a multi-cellular lung model (16HBE14o-, macrophages, and dendritic cells) was exposed in a mobile cell exposure system. Cells were exposed on up to three consecutive days each 12 h to ambient air from Fribourg, Switzerland, during summer and winter seasons. Higher particle number, particulate matter mass, and nitrogen oxide levels were observed in winter ambient air compared to summer. Good cell viability was seen in cells exposed to summer air and short-term winter air, but cells exposed three days to winter air were compromised. Exposure of summer ambient air revealed no significant upregulation of oxidative stress or pro-inflammatory genes. On the opposite, the winter ambient air exposure led to an increased oxidative stress after two exposure days, and an increase in three assessed pro-inflammatory genes already after 12 h of exposure. We found that even with a short exposure time of 12 h adverse effects in vitro were observed only during exposure to winter but not summer ambient air. With this work we have demonstrated that our simple, fast, and cost-effective approach can be used to assess (adverse) effects of ambient air.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Técnicas de Cultura de Células , Células Epiteliais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Dióxido de Nitrogênio/toxicidade , Ozônio/toxicidade , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cidades , Citocinas/genética , Monitoramento Ambiental/métodos , Células Epiteliais/metabolismo , Heme Oxigenase-1/genética , Humanos , Pulmão/citologia , Macrófagos/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , Dióxido de Nitrogênio/análise , Estresse Oxidativo/efeitos dos fármacos , Ozônio/análise , Estações do Ano , Suíça
6.
Environ Res ; 151: 789-796, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27670152

RESUMO

Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almost all gasoline cars can drive with fuel containing 10% ethanol (E10), flex-fuel cars can even use 85% ethanol (E85). Brazil and the USA already include 10-27% ethanol in their standard fuel by law. Most health effect studies on car emissions are however performed with diesel exhausts, and only few data exists for other fuels. In this work we investigated possible toxic effects of exhaust aerosols from ethanol-gasoline blends using a multi-cellular model of the human lung. A flex-fuel passenger car was driven on a chassis dynamometer and fueled with E10, E85, or pure gasoline (E0). Exhausts obtained from a steady state cycle were directly applied for 6h at a dilution of 1:10 onto a multi-cellular human lung model mimicking the bronchial compartment composed of human bronchial cells (16HBE14o-), supplemented with human monocyte-derived dendritic cells and monocyte-derived macrophages, cultured at the air-liquid interface. Biological endpoints were assessed after 6h post incubation and included cytotoxicity, pro-inflammation, oxidative stress, and DNA damage. Filtered air was applied to control cells in parallel to the different exhausts; for comparison an exposure to diesel exhaust was also included in the study. No differences were measured for the volatile compounds, i.e. CO, NOx, and T.HC for the different ethanol supplemented exhausts. Average particle number were 6×102 #/cm3 (E0), 1×105 #/cm3 (E10), 3×103 #/cm3 (E85), and 2.8×106 #/cm3 (diesel). In ethanol-gasoline exposure conditions no cytotoxicity and no morphological changes were observed in the lung cell cultures, in addition no oxidative stress - as analyzed with the glutathione assay - was measured. Gene expression analysis also shows no induction in any of the tested genes, including mRNA levels of genes related to oxidative stress and pro-inflammation, as well as indoleamine 2,3-dioxygenase 1 (IDO-1), transcription factor NFE2-related factor 2 (NFE2L2), and NAD(P)H dehydrogenase [quinone] 1 (NQO1). Finally, no DNA damage was observed with the OxyDNA assay. On the other hand, cell death, oxidative stress, as well as an increase in pro-inflammatory cytokines was observed for cells exposed to diesel exhaust, confirming the results of other studies and the applicability of our exposure system. In conclusion, the tested exhausts from a flex-fuel gasoline vehicle using different ethanol-gasoline blends did not induce adverse cell responses in this acute exposure. So far ethanol-gasoline blends can promptly be used, though further studies, e.g. chronic and in vivo studies, are needed.


Assuntos
Etanol/toxicidade , Gasolina/toxicidade , Substâncias Perigosas/toxicidade , Pulmão/efeitos dos fármacos , Modelos Biológicos , Emissões de Veículos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Adutos de DNA/metabolismo , Células Dendríticas/citologia , Células Epiteliais/citologia , Etanol/análise , Gasolina/análise , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Substâncias Perigosas/análise , Humanos , Pulmão/metabolismo , Pulmão/ultraestrutura , Macrófagos/citologia , Microscopia Confocal , Emissões de Veículos/análise
7.
Arch Toxicol ; 90(7): 1541-53, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27165416

RESUMO

Diesel engine emissions are among the most prevalent anthropogenic pollutants worldwide, and with the growing popularity of diesel-fueled engines in the private transportation sector, they are becoming increasingly widespread in densely populated urban regions. However, a large number of toxicological studies clearly show that diesel engine emissions profoundly affect human health. Thus the interest in the molecular and cellular mechanisms underlying these effects is large, especially concerning the nature of the components of diesel exhaust responsible for the effects and how they could be eliminated from the exhaust. This review describes the fundamental properties of diesel exhaust as well as the human respiratory tract and concludes that adverse health effects of diesel exhaust not only emerge from its chemical composition, but also from the interplay between its physical properties, the physiological and cellular properties, and function of the human respiratory tract. Furthermore, the primary molecular and cellular mechanisms triggered by diesel exhaust exposure, as well as the fundamentals of the methods for toxicological testing of diesel exhaust toxicity, are described. The key aspects of adverse effects induced by diesel exhaust exposure described herein will be important for regulators to support or ban certain technologies or to legitimate incentives for the development of promising new technologies such as catalytic diesel particle filters.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Mucosa Respiratória/efeitos dos fármacos , Doenças Respiratórias/induzido quimicamente , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/química , Animais , Dano ao DNA , Humanos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/química , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Pneumonia/patologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Doenças Respiratórias/metabolismo , Doenças Respiratórias/patologia , Propriedades de Superfície , Emissões de Veículos/análise
8.
J Chem Inf Model ; 54(6): 1553-7, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24826842

RESUMO

GPR139 is an orphan G protein-coupled receptor expressed mainly in the central nervous system. We developed a pharmacophore model based on known GPR139 surrogate agonists which led us to propose aromatic-containing dipeptides as potential ligands. Upon testing, the dipeptides demonstrated agonism in the Gq pathway. Next, in testing all 20 proteinogenic l-α-amino acids, L-tryptophan and l-phenylalanine were found to have EC50 values of 220 and 320 µM, respectively, making them the first putative endogenous agonists for GPR139.


Assuntos
Aminoácidos Aromáticos/química , Aminoácidos Aromáticos/farmacologia , Dipeptídeos/química , Dipeptídeos/farmacologia , Desenho de Fármacos , Proteínas do Tecido Nervoso/agonistas , Receptores Acoplados a Proteínas G/agonistas , Desenho Assistido por Computador , Células HEK293 , Humanos , Modelos Moleculares , Proteínas do Tecido Nervoso/metabolismo , Fenilalanina/química , Fenilalanina/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Triptofano/química , Triptofano/farmacologia
9.
Environ Toxicol Pharmacol ; 98: 104079, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36796551

RESUMO

Building demolition following domestic fires or abrasive processing after thermal recycling can release particles harmful for the environment and human health. To mimic such situations, particles release during dry-cutting of construction materials was investigated. A reinforcement material consisting of carbon rods (CR), carbon concrete composite (C³) and thermally treated C³ (ttC³) were physicochemically and toxicologically analyzed in monocultured lung epithelial cells, and co-cultured lung epithelial cells and fibroblasts at the air-liquid interface. C³ particles reduced their diameter to WHO fibre dimensions during thermal treatment. Caused by physical properties or by polycyclic aromatic hydrocarbons and bisphenol A found in the materials, especially the released particles of CR and ttC³ induced an acute inflammatory response and (secondary) DNA damage. Transcriptome analysis indicated that CR and ttC³ particles carried out their toxicity via different mechanisms. While ttC³ affected pro-fibrotic pathways, CR was mostly involved in DNA damage response and in pro-oncogenic signaling.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Tamanho da Partícula , Pulmão , Células Epiteliais , Hidrocarbonetos Policíclicos Aromáticos/análise , Inflamação/metabolismo , Dano ao DNA , Materiais de Construção , Fibroblastos
10.
Environ Health Perspect ; 130(2): 27003, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35112925

RESUMO

BACKGROUND: Secondary organic aerosols (SOAs) formed from anthropogenic or biogenic gaseous precursors in the atmosphere substantially contribute to the ambient fine particulate matter [PM ≤2.5µm in aerodynamic diameter (PM2.5)] burden, which has been associated with adverse human health effects. However, there is only limited evidence on their differential toxicological impact. OBJECTIVES: We aimed to discriminate toxicological effects of aerosols generated by atmospheric aging on combustion soot particles (SPs) of gaseous biogenic (ß-pinene) or anthropogenic (naphthalene) precursors in two different lung cell models exposed at the air-liquid interface (ALI). METHODS: Mono- or cocultures of lung epithelial cells (A549) and endothelial cells (EA.hy926) were exposed at the ALI for 4 h to different aerosol concentrations of a photochemically aged mixture of primary combustion SP and ß-pinene (SOAßPIN-SP) or naphthalene (SOANAP-SP). The internally mixed soot/SOA particles were comprehensively characterized in terms of their physical and chemical properties. We conducted toxicity tests to determine cytotoxicity, intracellular oxidative stress, primary and secondary genotoxicity, as well as inflammatory and angiogenic effects. RESULTS: We observed considerable toxicity-related outcomes in cells treated with either SOA type. Greater adverse effects were measured for SOANAP-SP compared with SOAßPIN-SP in both cell models, whereas the nano-sized soot cores alone showed only minor effects. At the functional level, we found that SOANAP-SP augmented the secretion of malondialdehyde and interleukin-8 and may have induced the activation of endothelial cells in the coculture system. This activation was confirmed by comet assay, suggesting secondary genotoxicity and greater angiogenic potential. Chemical characterization of PM revealed distinct qualitative differences in the composition of the two secondary aerosol types. DISCUSSION: In this study using A549 and EA.hy926 cells exposed at ALI, SOA compounds had greater toxicity than primary SPs. Photochemical aging of naphthalene was associated with the formation of more oxidized, more aromatic SOAs with a higher oxidative potential and toxicity compared with ß-pinene. Thus, we conclude that the influence of atmospheric chemistry on the chemical PM composition plays a crucial role for the adverse health outcome of emissions. https://doi.org/10.1289/EHP9413.


Assuntos
Poluentes Atmosféricos , Fuligem , Aerossóis/análise , Idoso , Envelhecimento , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Células Endoteliais/química , Células Endoteliais/metabolismo , Humanos , Pulmão/metabolismo , Material Particulado/análise
11.
Environ Int ; 166: 107366, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35763991

RESUMO

The health effects of exposure to secondary organic aerosols (SOAs) are still limited. Here, we investigated and compared the toxicities of soot particles (SP) coated with ß-pinene SOA (SOAßPin-SP) and SP coated with naphthalene SOA (SOANap-SP) in a human bronchial epithelial cell line (BEAS-2B) residing at the air-liquid interface. SOAßPin-SP mostly contained oxygenated aliphatic compounds from ß-pinene photooxidation, whereas SOANap-SP contained a significant fraction of oxygenated aromatic products under similar conditions. Following exposure, genome-wide transcriptome responses showed an Nrf2 oxidative stress response, particularly for SOANap-SP. Other signaling pathways, such as redox signaling, inflammatory signaling, and the involvement of matrix metalloproteinase, were identified to have a stronger impact following exposure to SOANap-SP. SOANap-SP also induced a stronger genotoxicity response than that of SOAßPin-SP. This study elucidated the mechanisms that govern SOA toxicity and showed that, compared to SOAs derived from a typical biogenic precursor, SOAs from a typical anthropogenic precursor have higher toxicological potency, which was accompanied with the activation of varied cellular mechanisms, such as aryl hydrocarbon receptor. This can be attributed to the difference in chemical composition; specifically, the aromatic compounds in the naphthalene-derived SOA had higher cytotoxic potential than that of the ß-pinene-derived SOA.

13.
Methods Mol Biol ; 2140: 199-215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32207114

RESUMO

Increasing ethical and biological concerns require a paradigm shift toward animal-free testing strategies for drug testing and hazard assessments. To this end, the application of bioprinting technology in the field of biomedicine is driving a rapid progress in tissue engineering. In particular, standardized and reproducible in vitro models produced by three-dimensional (3D) bioprinting technique represent a possible alternative to animal models, enabling in vitro studies relevant to in vivo conditions. The innovative approach of 3D bioprinting allows a spatially controlled deposition of cells and biomaterial in a layer-by-layer fashion providing a platform for engineering reproducible models. However, despite the promising and revolutionizing character of 3D bioprinting technology, standardized protocols providing detailed instructions are lacking. Here, we provide a protocol for the automatized printing of simple alveolar, bronchial, and intestine epithelial cell layers as the basis for more complex respiratory and gastrointestinal tissue models. Such systems will be useful for high-throughput toxicity screening and drug efficacy evaluation.


Assuntos
Materiais Biocompatíveis , Bioimpressão/métodos , Células Epiteliais , Impressão Tridimensional , Engenharia Tecidual/métodos , Células A549 , Células Epiteliais Alveolares , Automação , Brônquios/citologia , Células CACO-2 , Avaliação Pré-Clínica de Medicamentos , Impedância Elétrica , Desenho de Equipamento , Trato Gastrointestinal/citologia , Humanos , Técnicas In Vitro , Mucosa Intestinal/citologia , L-Lactato Desidrogenase/análise , Microscopia Confocal , Microscopia de Fluorescência , Testes de Toxicidade
14.
Toxicol In Vitro ; 54: 189-193, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30290203

RESUMO

Positive controls are an important feature in experimental studies as they show the responsiveness of the model under investigation. An often applied reagent for a pro-inflammatory stimulus is the endotoxin lipopolysaccharide (LPS), which has been shown to induce a cytokine release by various cell cultures. The effect of LPS in monocultures of 16HBE14o-, a bronchial cell line, and of A549, an alveolar cell line, were compared in submerged and air-liquid interface cultures, as well as in co-cultures of the two epithelial cells with monocyte-derived macrophages and dendritic cells. The protein and mRNA levels of the two most relevant pro-inflammatory mediators, Tumor necrosis factor alpha (TNF) and Interleukin 8 (CXCL8), were measured after 4 h and 24 h exposure. 16HBE14o- cells alone as well as in co-cultures are non-responsive to an LPS stimulus, but an already increased basal expression of both pro-inflammatory mediators after prolonged time in culture was observed. In contrary, A549 in monocultures showed increased CXCL8 production at the gene and protein level after LPS exposure, while TNF-levels were below detection limit. In A549 co-cultured with immune cells both mediators were upregulated. This study shows the importance of a careful evaluation of the culture system used, including the application of positive controls. In addition, the use of co-cultures with immune cells more adequately reflects the inflammatory response upon exposure to toxicants.


Assuntos
Grupos Controle , Inflamação/induzido quimicamente , Lipopolissacarídeos/farmacologia , Testes de Toxicidade/métodos , Linhagem Celular , Técnicas de Cocultura , Humanos , Inflamação/genética , Inflamação/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Pulmão/citologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
Sci Rep ; 8(1): 2297, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29396482

RESUMO

A substantial amount of traffic-related particle emissions is released by gasoline cars, since most diesel cars are now equipped with particle filters that reduce particle emissions. Little is known about adverse health effects of gasoline particles, and particularly, whether a gasoline particle filter (GPF) influences the toxicity of gasoline exhaust emissions. We drove a dynamic test cycle with a gasoline car and studied the effect of a GPF on exhaust composition and airway toxicity. We exposed human bronchial epithelial cells (ECs) for 6 hours, and compared results with and without GPF. Two hours later, primary human natural killer cells (NKs) were added to ECs to form cocultures, while some ECs were grown as monocultures. The following day, cells were analyzed for cytotoxicity, cell surface receptor expression, intracellular markers, oxidative DNA damage, gene expression, and oxidative stress. The particle amount was significantly reduced due to GPF application. While most biological endpoints did not differ, oxidative DNA damage was significantly reduced in EC monocultures exposed to GPF compared to reference exhaust. Our findings indicate that a GPF has beneficial effects on exhaust composition and airway toxicity. Further studies are needed to assess long-term effects, also in other cell types of the lung.


Assuntos
Poluentes Atmosféricos/toxicidade , Carcinógenos Ambientais/toxicidade , Dano ao DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Filtração , Gasolina/toxicidade , Células Cultivadas , Técnicas de Cocultura , Humanos , Células Matadoras Naturais/fisiologia , Estresse Oxidativo
16.
Environ Pollut ; 235: 263-271, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29291526

RESUMO

Adverse effect studies of gasoline exhaust are scarce, even though gasoline direct injection (GDI) vehicles can emit a high number of particles. The aim of this study was to conduct an in vitro hazard assessment of different GDI exhausts using two different cell culture models mimicking the human airway. In addition to gasoline particle filters (GPF), the effects of two lubrication oils with low and high ash content were assessed, since it is known that oils are important contributors to exhaust emissions. Complete exhausts from two gasoline driven cars (GDI1 and GDI2) were applied for 6 h (acute exposure) to a multi-cellular human lung model (16HBE14o-cell line, macrophages, and dendritic cells) and a primary human airway model (MucilAir™). GDI1 vehicle was driven unfiltered and filtered with an uncoated and a coated GPF. GDI2 vehicle was driven under four settings with different fuels: normal unleaded gasoline, 2% high and low ash oil in gasoline, and 2% high ash oil in gasoline with a GPF. GDI1 unfiltered was also used for a repeated exposure (3 times 6 h) to assess possible adverse effects. After 6 h exposure, no genes or proteins for oxidative stress or pro-inflammation were upregulated compared to the filtered air control in both cell systems, neither in GDI1 with GPFs nor in GDI2 with the different fuels. However, the repeated exposure led to a significant increase in HMOX1 and TNFa gene expression in the multi-cellular model, showing the responsiveness of the system towards gasoline engine exhaust upon prolonged exposure. The reduction of particles by GPFs is significant and no adverse effects were observed in vitro during a short-term exposure. On the other hand, more data comparing different lubrication oils and their possible adverse effects are needed. Future experiments also should, as shown here, focus on repeated exposures.


Assuntos
Poluentes Atmosféricos/toxicidade , Gasolina/toxicidade , Pulmão/efeitos dos fármacos , Emissões de Veículos/toxicidade , Linhagem Celular , Humanos , Macrófagos , Estresse Oxidativo
17.
Environ Pollut ; 238: 977-987, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29455917

RESUMO

Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases. It is further postulated similar exposure to volcanic ash can also affect such disease states. Understanding of the impact of combined exposure of volcanic ash and anthropogenic pollution to human health, however, remains limited. The aim of this study was to assess the biological impact of combined exposure to respirable volcanic ash (from Soufrière Hills volcano (SHV), Montserrat and Chaitén volcano (ChV), Chile; representing different magmatic compositions and eruption styles) and freshly-generated complete exhaust from a gasoline vehicle. A multicellular human lung model (an epithelial cell-layer composed of A549 alveolar type II-like cells complemented with human blood monocyte-derived macrophages and dendritic cells cultured at the air-liquid interface) was exposed to diluted exhaust (1:10) continuously for 6 h, followed by immediate exposure to the ash as a dry powder (0.54 ±â€¯0.19 µg/cm2 and 0.39 ±â€¯0.09 µg/cm2 for SHV and ChV ash, respectively). After an 18 h incubation, cells were exposed again for 6 h to diluted exhaust, and a final 18 h incubation (at 37 °C and 5% CO2). Cell cultures were then assessed for cytotoxic, oxidative stress and (pro-)inflammatory responses. Results indicate that, at all tested (sub-lethal) concentrations, co-exposures with both ash samples induced no significant expression of genes associated with oxidative stress (HMOX1, NQO1) or production of (pro-)inflammatory markers (IL-1ß, IL-8, TNF-α) at the gene and protein levels. In summary, considering the employed experimental conditions, combined exposure of volcanic ash and gasoline vehicle exhaust has a limited short-term biological impact to an advanced lung cell in vitro model.


Assuntos
Poluentes Atmosféricos/análise , Exposição por Inalação/análise , Emissões de Veículos/análise , Erupções Vulcânicas , Poluentes Atmosféricos/toxicidade , Respiração Celular , Chile , Células Epiteliais , Gasolina/toxicidade , Humanos , Exposição por Inalação/estatística & dados numéricos , Pulmão/efeitos dos fármacos , Macrófagos , Estresse Oxidativo , Respiração , Emissões de Veículos/toxicidade , Índias Ocidentais
18.
Toxicol In Vitro ; 45(Pt 1): 101-110, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28843492

RESUMO

Air pollution exposure, including passenger car emissions, may cause substantial respiratory health effects and cancer death. In western countries, the majority of passenger cars are driven by gasoline fuel. Recently, new motor technologies and ethanol fuels have been introduced to the market, but potential health effects have not been thoroughly investigated. We developed and verified a coculture model composed of bronchial epithelial cells (ECs) and natural killer cells (NKs) mimicking the human airways to compare toxic effects between pure gasoline (E0) and ethanol-gasoline-blend (E85, 85% ethanol, 15% gasoline) exhaust emitted from a flexfuel gasoline car. We drove a steady state cycle, exposed ECs for 6h and added NKs. We assessed exhaust effects in ECs alone and in cocultures by RT-PCR, flow cytometry, and oxidative stress assay. We found no toxic effects after exposure to E0 or E85 compared to air controls. Comparison between E0 and E85 exposure showed a weak association for less oxidative DNA damage after E85 exposure compared to E0. Our results indicate that short-term exposure to gasoline exhaust may have no major toxic effects in ECs and NKs and that ethanol as part of fuel for gasoline cars may be favorable.


Assuntos
Poluição do Ar , Etanol/toxicidade , Gasolina/toxicidade , Emissões de Veículos/toxicidade , Poluentes Atmosféricos , Brônquios , Técnicas de Cocultura , Células Epiteliais , Humanos , Células Matadoras Naturais
19.
Chem Commun (Camb) ; 52(69): 10537-9, 2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27491621

RESUMO

The chaperonin thermosome (THS) is a protein cage that lacks binding sites for metal ions and inorganic nanoparticles. However, when poly(amidoamine) (PAMAM) is encapsulated into THS, gold nanoparticles (AuNP) can be prepared in the THS. The polymer binds HAuCl4. Subsequent reduction yields nanoparticles with narrow size distribution in the protein-polymer conjugate.


Assuntos
Cloretos/química , Dendrímeros/química , Compostos de Ouro/química , Ouro/química , Nanopartículas Metálicas/química , Poliaminas/química , Termossomos/química , Tamanho da Partícula , Thermoplasma
20.
Sci Rep ; 6: 36681, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27830715

RESUMO

GPR139 is an orphan class A G protein-coupled receptor found mainly in the central nervous system. It has its highest expression levels in the hypothalamus and striatum, regions regulating metabolism and locomotion, respectively, and has therefore been suggested as a potential target for obesity and Parkinson's disease. The two aromatic amino acids L-Trp and L-Phe have been proposed as putative endogenous agonists, and three structurally related benzohydrazide, glycine benzamide, and benzotriazine surrogate agonist series have been published. Herein, we assayed 158 new analogues selected from a pharmacophore model, and identified 12 new GPR139 agonists, containing previously untested bioisosteres. Furthermore, we present the first combined structure-activity relationships, and a refined pharmacophore model to serve as a rationale for future ligand identification and optimization.


Assuntos
Hidrazinas/química , Modelos Químicos , Modelos Moleculares , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/química , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Triazinas/química , Animais , Células CHO , Cricetulus , Humanos , Proteínas do Tecido Nervoso/genética , Receptores Acoplados a Proteínas G/genética , Relação Estrutura-Atividade
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