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1.
Aquat Toxicol ; 226: 105565, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32682195

RESUMO

Pyrene (PYR) and fluorene (FLU) are among the sixteen priority Polycyclic Aromatic Hydrocarbons (PAH) of the United States Environmental Protection Agency and are both frequently detected in contaminated sites. Due to the importance of bivalve mollusks in biomonitoring programs and the scarce information on the biotransformation system in these organisms, the aim of this study was to investigate the effect of PYR and FLU at the transcriptional level and the enzymatic activities of some biotransformation systems in the Pacific oyster Crassostrea gigas, and to evaluate the histological effects in their soft tissues. Oysters C. gigas were exposed for 24 h and 96 h to PYR (0.25 and 0.5 µM) and FLU (0.6 and 1.2 µM). After exposure, transcript levels of cytochrome P450 coding genes (CYP1-like, CYP2-like, CYP2AU2, CYP356A1, CYP17α-like), glutathione S tranferase genes (omega GSTO-like and microsomal, MGST-like) and sulfotransferase gene (SULT-like), and the activity of ethoxyresorufin O-deethylase (EROD), Glutathione S-transferase (GST) and microssomal GST (MGST) were evaluated in gills. Histologic changes were also evaluated after the exposure period. PYR and FLU bioconcentrated in oyster soft tissues. The half-life time of PYR in water was lower than fluorene, which is in accordance to the higher lipophilicity and bioconcentration of the former. EROD activity was below the limit of detection in all oysters exposed for 96 h to PYR and FLU. The reproductive stage of the oysters exposed to PYR was post-spawn. Exposure to PYR caused tubular atrophy in digestive diverticula, but had no effect on transcript levels of biotransformation genes. However, the organisms exposed for 96 h to PYR 0.5 µM showed higher MGST activity, suggesting a protective role against oxidative stress in gills of oysters under higher levels of PYR in the tissues. Increased number of mucous cells in mantle were observed in oysters exposed to the higher FLU concentration, suggesting a defense mechanisms. Oysters exposed for 24 h to FLU 1.2 µM were in the ripe stage of gonadal development and showed higher transcript levels of CYP2AU2, GSTO-like and SULT-like genes, suggesting a role in the FLU biotransformation. In addition, after 96 h of exposure to FLU there was a significant increase of mucous cells in the mantle of oysters but no effect was observed on the EROD, total GST and MGST activities. These results suggest that PAH have different effects on transcript levels of biotransformation genes and enzyme activities, however these differences could also be related to the reproductive stage.


Assuntos
Crassostrea/efeitos dos fármacos , Fluorenos/toxicidade , Pirenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biotransformação/efeitos dos fármacos , Crassostrea/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Fluorenos/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirenos/metabolismo , Poluentes Químicos da Água/metabolismo
2.
Ecotoxicol Environ Saf ; 202: 110889, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623235

RESUMO

Coke oven emissions (COEs) can cause oxidative stress of the body, which in turn induces the occupational lung disease and also increases the risk of other diseases. COEs are the major occupational hazard factors for coke oven workers. The aim of the study is to explore the influences of COEs exposure on oxidative damage and estimate the benchmark dose (BMD) of COEs. A group of 542 workers exposed to COEs and 237 healthy controls from the same city were recruited in this study. The corresponding measuring kits were used to determine the plasma biomarkers of oxidative damage level. Generalized linear models and trend tests were used to analyze the relationship between COEs exposure and biomarkers. EPA Benchmark Dose Software was performed to calculate BMD and the lower confidence limit of the benchmark dose (BMDL) of COEs exposure. A significant association was observed between COEs exposure and oxidative damage with T-AOC as a biomarker. The BMD of COEs exposure were 2.83 mg/m3 and 1.39 mg/m3 for males and females, respectively, and the corresponding BMDL were 1.47 mg/m3 and 0.75 mg/m3, respectively. Our results suggested that the exposure level of COEs below the current national occupational exposure limits (OELs) would induce oxidative damage, and the OEL of COEs based on the T-AOC damage was suggested at 0.03 mg/m3 in this study.


Assuntos
Coque/toxicidade , Doenças Profissionais/metabolismo , Exposição Ocupacional/análise , Estresse Oxidativo/fisiologia , Adulto , Grupo com Ancestrais do Continente Asiático , Benchmarking , Biomarcadores/metabolismo , Coque/análise , Dano ao DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/estatística & dados numéricos , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos/análise , Resíduos
3.
Bull Environ Contam Toxicol ; 105(1): 86-94, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32577782

RESUMO

The distribution, seasonal variation and sources of 16 polycyclic aromatic hydrocarbons (PAH) from suspended particulate matter (SPM) of the Aurá River, a small amazon typical river located in Northern Brazil, were determined. Gas chromatography-mass spectrometry analysis of SPM revealed a mixture of PAH from different origins and a seasonal variation of PAH primary source for the studied area. Pyrene was the dominant PAH in both studied periods. Total PAH content (ΣPAH) ranged from lower than quantification limit (< LOQ) to 2498.2 ng g-1 dw during the dry season and < LOQ to 2865.8 ng g-1 dw during the wet season. Low molecular weight PAH (LMW) represented 51% of ΣPAH during the dry season and 29% during the wet season. It was noted, by comparing previous data, that the main source of these compounds was altered after the deactivation of an irregular landfill next to the river.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Brasil , China , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Material Particulado/análise , Pirenos , Rios/química , Estações do Ano , Urbanização
4.
Environ Pollut ; 265(Pt A): 114887, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505933

RESUMO

Organic contaminations and heavy metals in soils cause large harm to human and environment, which could be remedied by planting specific plants. The biochars produced by crop straws could provide substantial benefits as a soil amendment. In the present study, biochars based on wheat, corn, soybean, cotton and eggplant straws were produced. The eggplant straws based biochar (ESBC) represented higher Cd and pyrene adsorption capacity than others, which was probably owing to the higher specific surface area and total pore volume, more functional groups and excellent crystallization. And then, ESBC amendment hybrid Ryegrass (Lolium perenne L.) cultivation were investigated to remediate the Cd and pyrene co-contaminated soil. With the leaching amount of 100% (v/w, mL water/g soil) and Cd content of 16.8 mg/kg soil, dosing 3% ESBC (wt%, biochar/soil) could keep 96.2% of the Cd in the 10 cm depth soil layer where the ryegrass root could reach, and it positively help root adsorb contaminations. Compared with the single planting ryegrass, the Cd and pyrene removal efficiencies significantly increased to 22.8% and 76.9% by dosing 3% ESBC, which was mainly related with the increased plant germination of 80% and biomass of 1.29 g after 70 days culture. When the ESBC dosage increased to 5%, more free radicals were injected and the ryegrass germination and biomass decreased to 65% and 0.986 g. Furthermore, when the ESBC was added into the ryegrass culture soil, the proportion of Cd and pyrene degrading bacteria Pseudomonas and Enterobacter significantly increased to 4.46% and 3.85%, which promoted the co-contaminations removal. It is suggested that biochar amendment hybrid ryegrass cultivation would be an effective method to remediate the Cd and pyrene co-contaminated soil.


Assuntos
Lolium , Poluentes do Solo/análise , Bactérias , Biodegradação Ambiental , Cádmio/análise , Carvão Vegetal , Humanos , Pirenos , Solo
5.
Chemosphere ; 257: 127206, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32502737

RESUMO

Microplastics (MPs) could act as a vector for various kinds of pollutants due to their small size. Compared to nonpolar and nondegradabale MPs, the sorption of organic pollutants on polar and degradable MPs has been seldom studied. In this study, the sorption behavior of two nonpolar polycyclic aromatic hydrocarbons (PAHs, phenanthrene and pyrene), two polar derivates of PAHs (1-nitronapthalene and 1-napthylamine) and a heterocyclic chemical (atrazine) by three polar MPs including polybutylene succinate (PBS), polycaprolactone (PCL) and polyurethane (PU) and a typical nonpolar MP, polystyrene (PS) were investigated. The sorption followed the pseudo-second-order kinetics and sorption equilibrium was achieved within 5 days. Sorption isotherms could be well fitted by both Linear (R2>0.946) and Freundich models (R2>0.945) and the values of nonlinear index (n) from Freundlich model in most cases were close to 1, suggesting that hydrophobic partition was a primary process controlling the sorption. The sorption coefficients (Kd) of the five organic compounds ranged from 29. 6 to 1.42 × 105 (L/kg). The log KOC/log KOW of PAHs and derivates of PAHs on polar MPs were greater than 1, especially for 1-naphthylamine (1.30-1.40), confirming the great contribution of hydrogen bonding. PU contains a benzene ring and showed greater sorption compared the other two polar MPs, indicating the existence of π (n) -π electron donor-acceptor interactions. Morevoer, the sorption of phenanthrene and pyrene on PU were better fitted by Langmuir model and the maximum adsorption capacities were 1.06 × 104 and 5.87 × 103 mg/kg, respectively.


Assuntos
Poluentes Ambientais/química , Microplásticos/química , Adsorção , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Compostos Orgânicos , Fenantrenos , Plásticos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poliestirenos , Poliuretanos , Pirenos
6.
Environ Pollut ; 265(Pt B): 114730, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470900

RESUMO

Airborne particulate matter (PM) contains numerous hazardous polycyclic aromatic hydrocarbons (PAHs) as well as their functionalized congeners. However, the lack of useful methods to identify the sources of PM has hindered the development of researches in atmospheric and public health fields. This report proposes a new method for estimating the source contribution of combustion-derived particulate (Pc) by using 1-nitropyrene (1-NP) and pyrene (Pyr) as markers. This is premised on the fact that the formation of nitrogen oxides in the flame gas and the subsequent nitration of PAHs are functions of combustion temperature and therefore the concentration ratios of NPAHs to PAHs are highly temperature dependent. This method divides combustion sources into two groups - high and low temperatures - which here are respectively represented by automobile engine and coal combustion in urban areas. Formulae are derived for combustion-derived particulate (Pc), whose fraction in the total particulate is y (0 < y < 1), and particulates from combustion sources with high temperatures (Ph), whose fraction in Pc is x (0 < x < 1), and low temperatures (Pl), whose fraction is (1 -x). When concentrations of 1-NP and Pyr in Ph and Pl are known, values x and y can be calculated from the formulae by determining atmospheric 1-NP and Pyr concentrations at monitoring sites. Then atmospheric concentrations of Pc, Ph and Pl can be calculated. The proposed method has been applied for total suspended particulate matter (TSP) samples collected in Kanazawa and Kitakyushu (Japan) and Beijing (China) having different types of atmospheric pollution to clarify the change of contributions of automobiles and coal combustion.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Pequim , China , Carvão Mineral/análise , Monitoramento Ambiental , Japão , Material Particulado/análise , Pirenos
7.
Chemosphere ; 252: 126590, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443271

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in various environmental media and have thus attracted extensive attention worldwide. To prevent and control PAH pollution in China, the study of ambient water quality criteria (AWQC), human health risks, and aquatic ecological risk is critical. There are no reports to date on the human health AWQC of PAHs in China. Therefore, this study first derived the human health AWQC values of 12 PAHs based on exposure data and bioaccumulation factor in China. We found that local exposure parameters and other relevant factors were key during the development of AWQC in different countries and regions, which led to differences with the reference value recommended by USEPA. Based on the incremental life time cancer risk (ILCR), hazard quotients (HQ) and potentially affected fraction (PAF) methods, the health and ecological risks of 16 PAHs were assessed subsequently. And the results are as follows: the non-carcinogenic PAHs' health risks ranged from 1.01 × 10-10 to 1.60 × 10-9, and carcinogenic PAH health risks ranged from 5.03 × 10-7 to 4.74 × 10-5. The toxic effects of 8 PAHs on aquatic organisms exhibited the following order: benzo (a) pyrene (BaP) > anthracene (Ant) > pyrene (Pye) > phenanthrene (Phe) > fluoranthene (Flua) > acenaphthene (Ace) > fluorene (Flu) > naphthalene (Nap). Among these, the ecological risks posed by Ant and BaP were the highest, according to the HQ and PAF methods.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes da Água/análise , Poluição Química da Água/estatística & dados numéricos , Benzo(a)pireno , Carcinógenos/análise , China , Fluorenos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fenantrenos , Pirenos , Medição de Risco , Qualidade da Água
8.
Chemosphere ; 255: 126955, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32416390

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) can induce skin toxicity. Although some investigations have been conducted to assess the skin toxicity of different PAHs, few comparisons using a series of PAHs with different ring numbers and arrangements have been done. We aimed to explore the skin absorption of 6 PAH compounds and their effect on cutaneous inflammation. In vitro skin permeation was rated by Franz cell with pig skin. Molecular docking was employed to compute the PAH interaction with stratum corneum (SC) lipids. Cultured keratinocytes were exposed to PAHs for analyzing cytotoxicity, cyclooxygenase (COX)-2, prostaglandin E2 (PGE2), chemokines, and differentiation proteins. The in vivo topical PAH exposure in mice was characterized by skin absorption, transepidermal water loss (TEWL), PGE2 level, and histology. The skin deposition from the aqueous vehicle increased following the increase of PAH lipophilicity and molecular size, with benzo[a]pyrene (5-ring PAH) showing the greatest absorption. Pyrene was the compound showing the highest penetration across the skin (flux). Although the PAHs fluoranthene, pyrene, chrysene, and 1,2-benzanthracene all had 4 rings, the skin permeation was quite different. 1,2-Benzanthracene showed the greatest absorption among the 4-ring compounds. The PAHs with higher absorption exhibited stronger interaction with SC lipids according to the in silico modeling. Chrysene and 1,2-benzanthracene generally showed the highest COX-2 and PGE2 expression, followed by benzo[a]pyrene. The lowest COX-2 and PGE2 upregulation was observed for naphthalene (2-ring PAH). A contrary tendency was detected for the upregulation of chemokines. Filaggrin and integrin ß1 in keratinocytes were suppressed at a comparable level by all PAHs. The skin's absorption of PAHs showed strong in vivo-in vitro correlation. 1,2-Benzanthracene and benzo[a]pyrene highly disrupted the skin barrier and elevated the inflammation in vivo. The tendency toward in vivo inflammation caused by various PAHs could be well predicted by the combined estimation using in vitro skin absorption and a keratinocyte bioassay. This study also established the structure-permeation relationship (SPR) of PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Absorção Cutânea , Pele/metabolismo , Animais , Benzo(a)Antracenos , Benzo(a)pireno/toxicidade , Crisenos , Inflamação/metabolismo , Queratinócitos , Camundongos , Simulação de Acoplamento Molecular , Naftalenos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Pirenos , Suínos
9.
Ecotoxicol Environ Saf ; 200: 110780, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470683

RESUMO

A green synthesis method for nanoscale silver using ß-cyclodextrin as both reducing agent and stabilizer was developed. ß-cyclodextrin was used not only as a reducing agent but also a stabilizing agent for nano-silver, and is also an excellent detection substrate due to its special structure (inner hydrophobic and outer hydrophilic ring structure). Then, the green synthesized silver nanoparticles were used as Surface-enhanced Raman spectroscopy (SERS) enhanced substrates to detect polycyclic aromatic hydrocarbons, such as: anthracene, pyrene, chrysene and triphenylene. The SERS substrate can be used for both quantitative detection of the four polycyclic aromatic hydrocarbons and qualitative identification of mixtures of these hydrocarbons. This synthesis method is simple and convenient, having great potential in simultaneous and rapid detection of environmental organic pollutants.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Prata/química , Análise Espectral Raman/métodos , beta-Ciclodextrinas/química , Antracenos/análise , Crisenos/análise , Interações Hidrofóbicas e Hidrofílicas , Pirenos/análise
10.
Toxicol Appl Pharmacol ; 396: 114995, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32251684

RESUMO

Currently, the environmental impact of ubiquitous plastic debris triggered quite some public attention. However, the global impact of microplastic on human health is by and large either unknown or neglected. By looking at the underlying biochemical mechanisms leading to the global health threat microplastic was discovered to carry persistent organic pollutants, such as polycyclic aromatic hydrocarbons (PAH), to marine life. The effect of microplastic-ingestion in the human body remains unfortunately somewhat elusive as of yet. For this reason, we screened for compounds binding to the human estrogen receptor α (ERα) and identified the PAH compounds indeno[1,2,3-cd]pyrene (Indpy) and picene (Pice) with a high binding affinity. We applied next generation sequencing to analyze the differentially expressed genes in MCF-7 cells after treatment with Indpy and Pice. We found 8 upregulated genes: ABCC5, CCNG2, CYP1A1, DDIT4, IER3, RUNX2, STC2, and SLC7A5 and 14 downregulated genes: ADORA1, CEBPB, CELSR2, CTSD, CXCL12, KRT19, PGR, PKIB, RARA, RET, SEMA3B, SIAH2, TFAP2C, and XBP1 induced by both ligands and associated with ESR1-regulation. The altered gene expression may influence cell proliferation and metastasis, favoring cancer development with a poor response to therapy. In addition, we confirmed the binding of Indpy and Pice to ERα using molecular docking and microscale thermophoresis. ERα activation was measured with ESR1-overexpressing HEK293 (HEK-ESR1) cells and confirmed for Indpy. In conclusion, we showed an ESR1-mediated influence of the PAH compounds Indpy and Pice on the gene expression pattern of MCF-7 cells, possibly also promoting breast cancer development in patients.


Assuntos
Crisenos/farmacologia , Receptor alfa de Estrogênio/metabolismo , Expressão Gênica/efeitos dos fármacos , Pirenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7/efeitos dos fármacos , Simulação de Acoplamento Molecular , Reação em Cadeia da Polimerase em Tempo Real
11.
Sci Total Environ ; 725: 138542, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32304974

RESUMO

Polycyclic aromatic hydrocarbon (PAH)-DNA binding is an essential step in PAH-induced carcinogenesis. A large number of PAHs contain substituents, it is unclear whether functional groups will influence the PAH-DNA binding. Here, we investigated amino (-NH2) and hydroxy (-OH) substitution on pyrene-DNA binding. Because of the considerable effects of electrostatic surface potential (ESP), -NH2 substitution significantly facilitated binding by increasing the binding constant (log KA) from 4.14 L mol-1 to 12.31 L mol-1, while -OH substitution inhibited binding by reducing log KA to 3.68 L mol-1. Spectroscopy results revealed that pyrene and its derivatives were able to bind with thymine to induce DNA damage or double helix distortion. Quantum chemical calculations showed that -NH2 substitution induces hydrogen bond formation, thereby enhancing the binding of pyrene with DNA; moreover, binding force changes due to -OH substitution may not be an essential factor. All structural descriptors were not correlated with the quenching constant (KSV) or binding constant, indicating that changes in physicochemical properties shows no influence on pyrene-DNA binding. The results of this study will improve our understanding of the contribution of functional groups to PAH-DNA binding.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Pirenos , Dano ao DNA
12.
Chemosphere ; 254: 126861, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32348925

RESUMO

The remediation of cadmium-pyrene co-contaminated soil by electrokinetic (EK) and the influence factors were investigated in this study. The artificial contaminated soils were treated for 20 days in EK experimental setups without electrolyte solution reservoirs, to simulate in-situ remediation of unsaturated soil. The results indicated that polarity-reversing electric field had maintained soil pH in the range of 7.27-7.67. Cadmium (Cd) contaminant would aggregate near electrodes, and the average Cd concentration in these areas had reached 72.21 mg/kg (original 51.6 mg/kg), while the value in soil farthest away from electrodes was 33.58 mg/kg. The reasons for Cd aggregated were: the insoluble hydroxide formations attribute to the frequently alternation of acid-base environment, and the decrease of pH and water holding capacity in soil away from electrodes would promote the dissolved Cd movement by electro-osmosis flow. Although the applied electric field could promote the growth and activity of pyrene-degrading microorganisms (PDM), the soluble Cd would be the restriction factor, especially in soil near electrodes. However, the highest (56.38%) pyrene removal efficiency (PRE) was achieved near electrodes due to the synergistic effect of electric filed and PDM, and PRE was positively correlated with the PDM number in soil away from electrodes.


Assuntos
Cádmio/análise , Recuperação e Remediação Ambiental , Poluentes do Solo/análise , Ácidos , Eletricidade , Eletrodos , Poluição Ambiental , Concentração de Íons de Hidrogênio , Pirenos , Solo/química
13.
Wei Sheng Yan Jiu ; 49(2): 242-248, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32290940

RESUMO

OBJECTIVE: To understand the exposure levels of polycyclic aromatic hydrocarbons(PAHs) and the expression of interleukin-2(IL-2), interferon-γ(IFN-γ), interleukin-4(IL-4), interleukin-10(IL-10) in peripheral blood of coke oven workers exposed to coke oven emissions(COEs). The other purpose of this study was to understand the performance of IFN-γ and IL-10 epigenetic mechanisms in COEs exposure damage. METHODS: The 85 workers exposed to COEs in a coking plant were randomly selected as the exposure group. The 47 workers who were exposed to non-COEs in the coking plant were used as the control group. The morning urine of the exposure group and the control group were subjected to detection of 1-OHPyr levels with alkaline hydrolysis High-performance liquid chromatography fluorescence, urine creatinine correction. The peripheral venous blood were subjected to detection of the expression of IL-2, IFN-γ, IL-4 and IL-10 with enzyme-linked immunosorbent assay. And methylation levels of IFN-γ and IL-10 were analyzed by time of flight mass spectrometry. RESULTS: The urine 1-hyroxy-pyrene(1-OHPyr) content of coke oven workers was higher than that of the control group(F=12. 446, P<0. 05). The urine 1-OHPyr content of the furnace side and the furnace top were higher than the control group, and the differences were statistically significant. Compared with the control group, serum IL-2 content of coke oven workers decreased(F=14. 774, P<0. 05), and serum IFN-γ content of coke oven workers decreased(F=46. 379, P<0. 05), the serum IL-4 content of coke oven workers increased(F=17. 426, P<0. 05), the serum IL-10 content of coke oven workers increased(F=33. 515, P<0. 05), and the TH1/TH2 ratio of coke oven workers decreased(F=21. 677, P<0. 05). In the exposed group, the level of IFN-γ in the top of the furnace was higher than that in the bottom of the furnace. The difference was statistically significant. The level of IL-10 in the top and bottom of the furnace was lower than that in the furnace. The difference was statistically significant. The IL-10 CpG-11, CpG-15 and mean methylation rates in the exposed group were lower than those in the control group, and the differences were statistically significant. The methylation rate of IFN-γ CpG-5 in the exposed group was higher than that in the control group, and the difference was statistically significant. The urine 1-OHPyr content of coke oven workers was negatively correlated with TH1/TH2 ratio and IFN-γ expression level, and positively correlated with IL-4 and IL-10 levels. The IL-10 CpG-11, CpG-15 methylation rate decreased with increasing urine 1-OHPyr concentration. CONCLUSION: The side and top of the furnace worker exposed to COEs were the key targets for occupational health. The exposure of coke oven workers to COEs affected the expression of immunoregulatory cytokines. The exposure of COEs caused the change of IL-10 methylation rate.


Assuntos
Coque , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Citocinas , DNA , Dano ao DNA , Humanos , Metilação , Pirenos/análise
14.
Chemosphere ; 251: 126336, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32145574

RESUMO

1-Nitropyrene (1-NP) is a representative nitro-polycyclic aromatic hydrocarbon from diesel exhaust. Recently, we found that maternal 1-NP exposure caused fetal growth retardation and disturbed cognitive development in adolescent female offspring. To investigate long-term 1-NP exposure on spermatogenesis and steroidogenesis, male mice were exposed to 1-NP (1.0 mg/kg/day) by gavage for 70 days. There was no significant difference on relative testicular weight, number of testicular apoptotic cells and epididymal sperm count between 1-NP-exposed mice and controls. Although long-term 1-NP exposure did not influence number of Leydig cells, steroidogenic genes and enzymes, including STAR, P450scc, P45017α and 17ß-HD, were downregulated in 1-NP-expoed mouse testes. Correspondingly, serum and testicular testosterone (T) levels were reduced in 1-NP-exposed mice. Additional experiment showed that testicular GRP78 mRNA and protein were upregulated by 1-NP. Testicular phospho-IRE1α and sliced xbp-1 mRNA, a downstream molecule of IRE1α, were elevated in 1-NP-exposed mice. Testicular phospho-PERK and phospho-eIF2α, a downstream molecule of PERK pathway, were increased in 1-NP-exposed mice. Testicular NOX4, a subunit of NAPDH oxidase, and HO-1, MDA, two oxidative stress markers, were increased in 1-NP-exposed mice. Testicular GSH and GSH/GSSG were decreased in 1-NP-exposed mice. These results suggest that long-term 1-NP exposure induces reactive oxygen species-evoked ER stress and disrupts steroidogenesis in mouse testes.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Poluentes Ambientais/toxicidade , Pirenos/toxicidade , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Endorribonucleases , Epididimo , Feminino , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Tamanho do Órgão , Proteínas Serina-Treonina Quinases , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Testosterona/sangue
15.
Chemistry ; 26(22): 5075-5084, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32064675

RESUMO

Controlling the conformation and function of biomolecules through photoregulators holds great promise as a spatiotemporally controllable tool for disease control. In addition, introducing photoregulators into biomolecules has also found applications in constructing smart nanomaterials. In spite of the astonishing advances that have been made in the past few years, realizing highly controllable and efficient regulation over the conformation and function of biomolecules under physiological conditions is still challenging. Herein, sulfonated pyrene SPy was synthesized and used as a photoregulator to control the looping of single-stranded DNAs (ssDNAs) in aqueous solution. Due to its water solubility, SPy merits use in the study of biomolecules in aqueous solution. The looping of the doubly SPy-modified ssDNAs is stimulated by irradiation and regulated by SPy. Photoionization generates the radical cation of SPy (SPy.+ ). The association of SPy.+ with its neutral counterpart, SPy, gives rise to the dimer radical cation of SPy (SPy2 .+ ). During the association process, the stabilization energy released to form SPy2 .+ provides a driving force for the looping of ssDNAs. Conversely, the formed loop conformations were trapped by the formation of SPy2 .+ , and this allowed the looping dynamics to be investigated. The results reported herein suggest potential of SPy as a photoregulator for controlling the conformation and function of biomolecules under physiological conditions.


Assuntos
DNA/metabolismo , Pirenos/química , Compostos de Sulfidrila/química , Cátions , DNA/química , DNA de Cadeia Simples , Compostos de Sulfidrila/metabolismo
16.
Environ Pollut ; 260: 113995, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32004962

RESUMO

Telomeres are located at the end of eukaryotic chromosomes and vulnerable to exogenous chemical compounds. Exposure to coke oven emissions (COEs) leads to a dose-related telomere damage, and such chromosomal damage might trigger the cGAS/STING signaling pathway which plays an important role in immune surveillance. However, the relationship between the genetic variations in the cGAS/STING signaling pathway and telomere damage in the COEs-exposure workers has not been investigated. Therefore, we recruited 544 coke oven workers and 238 healthy control participants, and determined the level of COEs exposure, concentration of urinary 1-hydroxypyrene (1-OHPYR), genetic polymorphisms and telomere length. The results showed that the telomere length significantly decreased from the control-to high-exposure groups as defined by the external exposure level (P < 0.05). The results also indicated that STING rs7447927 CC, cGAS rs34413328 AA, and cGAS rs610913 AA could inhibit telomere shortening in the exposure group (P < 0.05), and cGAS rs34413328, urine 1-OHPYR and cumulative exposure dose (CED) had a significant association with telomere length by generalized linear model. In conclusion, telomere shortening was a combined consequence of short-term exposure, long-term exposure, and genetic variations among the COEs-exposure workers.


Assuntos
Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Coque , Dano ao DNA , Humanos , Nucleotidiltransferases , Polimorfismo Genético , Pirenos , Transdução de Sinais , Telômero/efeitos dos fármacos
17.
Environ Pollut ; 260: 113984, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32041019

RESUMO

1-nitropyrene (1-NP) is a key component of diesel exhaust-sourced fine particulate matter (PM2.5). Our recent study demonstrated that gestational 1-NP exposure caused placental proliferation inhibition and fetal intrauterine growth restriction (IUGR). This study aimed to investigate the role of genotoxic stress on 1-NP-induced placental proliferation inhibition and fetal IUGR. Human trophoblasts were exposed to 1-NP (10 µM). Growth index was reduced and PCNA was downregulated in 1-NP-exposed placental trophoblasts. More than 90% of 1-NP-exposed trophoblasts were arrested in either G0/G1 or G2/M phases. CDK1 and cyclin B, two G2/M cycle-related proteins, and CDK2, a G0/G1 cycle-related protein, were reduced in 1-NP-exposed trophoblasts. Phosphorylated Rb, a downstream molecule of CDK2, was inhibited in 1-NP-exposed trophoblasts. Moreover, DNA double-strand break was observed and γ-H2AX, another indicator of DNA double-strand break, was upregulated in 1-NP-exposed trophoblasts. Phosphorylated ATM, a key molecule of genotoxic stress, and its downstream molecule Chk2 were elevated. By contrast, Cdc25A, a downstream target of Chk2, was reduced in 1-NP-exposed trophoblasts. Phenyl-N-t-butylnitrone (PBN), a free radical scavenger, inhibited 1-NP-induced genotoxic stress and trophoblast cycle arrest. Animal experiment showed that N-acetylcysteine (NAC), an antioxidant, rescued 1-NP-induced placental proliferation inhibition and fetal IUGR in mice. These results provide evidence that reactive oxygen species (ROS)-mediated cellular genotoxic stress partially contributes to 1-NP-induced placental proliferation inhibition and fetal IUGR.


Assuntos
Retardo do Crescimento Fetal , Mutagênicos/toxicidade , Pirenos/toxicidade , Trofoblastos , Animais , Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Feminino , Humanos , Camundongos , Placenta , Gravidez , Pirenos/química , Espécies Reativas de Oxigênio/metabolismo
18.
Sci Total Environ ; 717: 137210, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062235

RESUMO

The risks of pollution by polycyclic aromatic hydrocarbons (PAHs) may increase in bioremediated soils as a result of the formation of toxic byproducts and the mobilization of pollutants associated to suspended colloids. In this study, we used the motile and chemotactic bacterium Pseudomonas putida G7 as an experimental model for examining the potential role of bacterial motility in the cometabolism and biosorption of pyrene in a porous medium. For this purpose, we conducted batch and column transport experiments with 14C-labelled pyrene loaded on silicone O-rings, which acted as a passive dosing system. In the batch experiments, we observed concentrations of the 14C-pyrene equivalents well above the equilibrium concentration observed in abiotic controls. This mobilization was attributed to biosorption and cometabolism processes occurring in parallel. HPLC quantification revealed pyrene concentrations well below the 14C-based quantifications by liquid scintillation, indicating pyrene transformation into water-soluble polar metabolites. The results from transport experiments in sand columns revealed that cometabolic-active, motile cells were capable of accessing a distant source of sorbed pyrene. Using the same experimental system, we also determined that salicylate-mobilized cells, inhibited for pyrene cometabolism, but mobilized due to their tactic behavior, were able to sorb the compound and mobilize it by biosorption. Our results indicate that motile bacteria active in bioremediation may contribute, through cometabolism and biosorption, to the risk associated to pollutant mobilization in soils. This research could be the starting point for the development of more efficient, low-risk bioremediation strategies of poorly bioavailable contaminants in soils.


Assuntos
Bactérias , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Porosidade , Pirenos , Poluentes do Solo
19.
Nucleic Acids Res ; 48(7): 3975-3986, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32095808

RESUMO

Guanine-rich regions of the human genome can adopt non-canonical secondary structures. Their role in regulating gene expression has turned them into promising targets for therapeutic intervention. Ligands based on polyaromatic moieties are especially suitable for targeting G-quadruplexes utilizing their size complementarity to interact with the large exposed surface area of four guanine bases. A predictable way of (de)stabilizing specific G-quadruplex structures through efficient base stacking of polyaromatic functional groups could become a valuable tool in our therapeutic arsenal. We have investigated the effect of pyrene-modified uridine nucleotides incorporated at several positions of the thrombin binding aptamer (TBA) as a model system. Characterization using spectroscopic and biophysical methods provided important insights into modes of interaction between pyrene groups and the G-quadruplex core as well as (de)stabilization by enthalpic and entropic contributions. NMR data demonstrated that incorporation of pyrene group into G-rich oligonucleotide such as TBA may result in significant changes in 3D structure such as formation of novel dimeric topology. Site specific structural changes induced by stacking of the pyrene moiety on nearby nucleobases corelate with distinct thrombin binding affinities and increased resistance against nuclease degradation.


Assuntos
Aptâmeros de Nucleotídeos/química , Quadruplex G , Pirenos/química , Aptâmeros de Nucleotídeos/sangue , Aptâmeros de Nucleotídeos/metabolismo , Desoxirribonucleases , Dimerização , Entropia , Humanos , Termodinâmica , Trombina/metabolismo , Nucleotídeos de Uracila/química
20.
Environ Res ; 183: 109219, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32085994

RESUMO

The Mixture exposure to pristine multi-walled carbon nanotubes (P-MWCNTs) and polycyclic aromatic hydrocarbons (PAHs) such as benzo α pyrene (BaP) in the environment is inevitable. Assessment toxicity of P-MWCNTs and BaP individually may not provide sufficient toxicological information. The objective of this work is to investigate the combined toxicity of P-MWCNTs and BaP in human epithelial lung cells (A549). The physico-chemical properties of P-MWCNTs were determined suing analytical instruments. The toxicity of P-MWCNTs and BaP on A549 lung cells individually or combined were assessed. For toxicity assessment, cell viability, ROS generation, oxidative DNA damage, and apoptosis experiments were conducted. The results of this study demonstrated that P-MWCNTs and BaP individually reduced cell viability in A549 lung cells, and oxidative stress was as the possible mechanism of cytotoxicity. The co-exposure to P-MWCNTs and BaP enhanced the cytotoxicity compared to exposure to P-MWCNTs and BaP individually, but not statistically significant. The two-factorial analysis demonstrated an additive toxicity interaction for co-exposure to P-MWCNTs and BaP. The complicated toxicity interaction among BaP with fibers and metal impurities of P-MWCNTS could be probable reasons for additive toxicity interaction. Results of this study could be helpful as the basis for future studies and risk assessment of co-exposure to MWCNTs and PAHs.


Assuntos
Benzo(a)pireno , Nanotubos de Carbono , Células A549 , Benzo(a)pireno/toxicidade , Sobrevivência Celular , Humanos , Pulmão/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Pirenos
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