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1.
J Environ Sci (China) ; 85: 208-219, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471028

RESUMO

Methyl tert-butyl ether (MTBE), as a widely used gasoline additive, is suspected of being environmentally toxic. MTBE accumulates mainly in adipose tissue, but its effect on obesity or obesity-related metabolic disorders has not been well understood yet. Therefore, we examined the effect of MTBE on the adipose function and the related metabolic processes with both 3T3-L1 cell line and C57BL/6J mice model. We found that exposure to MTBE at the environmental relevant concentration (100 µmol/L) could significantly induce differentiation of preadipocyte and disturb insulin-stimulated glucose uptake of mature adipocyte. The in vivo observation in male mice showed a positive correlation of visceral white adipose tissue (vWAT) expansion and cell size increase with MTBE treatment in 14 weeks. Glucose tolerance and insulin sensitivity tests demonstrated that MTBE at 1000 µg/(kg·day) disturbed the systemic glucose metabolism in a gender-specific manner, which might be partly attributed to the alterations of gut microbiota community at genus level with respect to Akkermansia, Clostridium XlVb, and Megamonas. In summary, our study characterized the effect of MTBE on adipose tissue function and glucose homeostasis in vitro and in vivo, and revealed that systemic disorders of the glucose metabolism might be modulated by the related gut microbiota.


Assuntos
Poluentes Atmosféricos/toxicidade , Metabolismo dos Carboidratos/efeitos dos fármacos , Éteres Metílicos/toxicidade , Animais , Gasolina , Glucose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Testes de Toxicidade
2.
J Environ Sci (China) ; 85: 94-106, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471036

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are subjected to various transformation processes (chemical, physical and biological processes) in the environment, potentially affecting their bioavailability and toxic properties. However, the size variation of TiO2 NPs during aging process and subsequent effects in mammalian cells are largely unknown. The aim of this study was to illustrate the adverse effects of TiO2 NPs in different sizes (5, 15 and <100 nm) during aging process on human-hamster hybrid (AL) cells. There was an aging-time dependent enhancement of average hydrodynamic size in TiO2 NPs stock suspensions. The cytotoxicity of fresh TiO2 NPs increased in a size-dependent manner; in contrast, their genotoxicity decreased with the increasing sizes of NPs. No significant toxicity difference was observed in cells exposed to either fresh or 60 day-aged TiO2 NPs. Both Fresh and aged TiO2 NPs efficiently induced mitochondrial dysfunction and activated Caspase-3/7 in a size-dependent manner. Using mitochondrial-DNA deficient (ρ0) AL cells, we further discovered that mitochondrial dysfunction made significant contribution to the size-dependent toxicity induced by TiO2 NPs during the aging process. Taken together, our data indicated that TiO2 NPs could significantly induced the cytotoxicity and genotoxicity in an aging time-independent and size-dependent manner, which were triggered by mitochondrial dysfunction. Our study suggested the necessity to include size as an additional parameter for the cautious monitoring of TiO2 NPs disposal before entering the environment.


Assuntos
Nanopartículas/toxicidade , Titânio/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Dano ao DNA , Humanos , Testes de Toxicidade
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(8): 843-850, 2019 Aug 06.
Artigo em Chinês | MEDLINE | ID: mdl-31378047

RESUMO

The number of new chemicals increases tremendously annually, while traditional time-and cost-consuming toxicity tests based on animals with the uncertainty of extrapolation could not meet the demand of hazard identification and risk assessment. Thus,the evolution of methodology for toxicity tests is desired to fill up the huge data gap. With the rapid development of life science and technology,the insights into the nature of life and pathology of diseases have changed and systematic toxicology has emerged. Equipping with the advantages of multi-disciplinary study,systematic toxicology expands the research fields of toxicology and accelerates the speed of illustrating molecular mechanism of environmental xenobiotics, biomarkers screening and validation, and the development of new methods for risk assessment. Toxicogenomics and computational toxicology analysis are the major technology of systematic toxicology. Computational toxicology integrates data from toxicogenomics to construct multi-levels and multi-dimensional models for quantitative exposure risk assessment. This research summarized the research progress of computational toxicology from the aspects of research strategies, common databases, analytical tools, research methods and application, so as to provide references for the risk assessment of chemical substances.


Assuntos
Medição de Risco/métodos , Testes de Toxicidade/métodos , Toxicologia/métodos , Animais , Biomarcadores , Projetos de Pesquisa , Toxicogenética
4.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2845-2853, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418211

RESUMO

The safety of feed derived from genetically modified (GM) crops is one of the focuses of attention. To evaluate the ecotoxicological effects of transgenic mCry1Ac maize (BT799) on fish, zebrafish (Danio rerio) were fed extruded feeds containing either 20% GM maize (GMF) or its parental control maize (PF), GM maize meal (GMM) or its parental control maize meal (PMM), and a control commercial feed (CF), respectively. The growth performance, histopathology, reproduction, antioxidant enzyme activity and mRNA expression levels of sensitive protein in the liver were investigated over the course of a 98-day feeding trial. The results showed that transgenic mCry1Ac maize had no significant effect on growth, histopathology of the liver, brain and intestinal tract, fecundity, hatching rate of fertilized eggs, superoxide dismutase (SOD), catalase (CAT) activity, mRNA expression levels of SOD and CAT, or heat shock protein 70 (HSP70) and vitellogenin (VTG) in the liver. However, zebrafish fed the commercial feed exhibited significantly greater weight, longer length, and higher specific growth rate than those fed feeds (GMF and PF) and maize meals (GMM and PMM). The hatching rate of zebrafish in the feed groups was significantly lower than that of the maize meal groups and the commercial feed group. The mRNA transcriptional levels of VTG were significantly higher in the liver for the feed groups (3.85±0.76) than that for the maize meal groups (1.60±0.56). These results suggest that transgenic mCry1Ac maize has no ecotoxicological effects on zebrafish. However, the differences in nutrient composition and palatability between the extruded experimental feeds and the commercial feed would lead to significant diffe-rences in some parameters.


Assuntos
Alimentos Geneticamente Modificados , Zea mays/genética , Ração Animal , Animais , Plantas Geneticamente Modificadas , Testes de Toxicidade , Peixe-Zebra/fisiologia
5.
Ecotoxicol Environ Saf ; 182: 109391, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31272020

RESUMO

Methyl-triclosan (MTCS) is a dominant transformation product of triclosan (TCS), which has been widely used as an effective antimicrobial ingredient with increasing concentrations in the environment. MTCS shows higher persistence in environment than its parent chemical TCS. The toxic effects of MTCS and toxicological mechanism are not well understood up to now. This study investigated the cytotoxic effects of MTCS in HepG2 cells in terms of cell viability, apoptosis induction, ROS production, GSH/GSSG levels, Mitochondrial Membrane Potential (MMP) reduction, LDH release, glucose uptake and ATP production. Moreover, the related gene transcripts were measured with RT-qPCR assay. Cytotoxic experiments in HepG2 cells revealed that MTCS exposure at micromol per liter levels had toxic effects as evidenced by decreased cell survival, elevated cell apoptosis, reduced MMP and increased LDH release. These toxic effects were associated with increased ROS production and reduced GSH/GSSG ratio. Meanwhile, elevated glucose uptake and ATP production indicated that MTCS induced membrane damages resulted not from a typical mitochondrial uncoupler, but from oxidative stress. Analysis of gene transcripts showed that MTCS exposure induced mRNA expressions alterations associated with oxidative stress response, energy production, cell cycle regulation and cell apoptosis. In general, the caspase-dependent mitochondrial apoptosis pathway might play a role in MTCS induced cytotoxicity in HepG2 cells.


Assuntos
Anti-Infecciosos Locais/toxicidade , Testes de Toxicidade , Triclosan/análogos & derivados , Apoptose/efeitos dos fármacos , Caspases , Pontos de Checagem do Ciclo Celular , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Triclosan/toxicidade
6.
Ecotoxicol Environ Saf ; 182: 109400, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276883

RESUMO

This study was designed to investigate skeletal changes in Podocnemis unifilis embryos derived from artificially incubated eggs exposed to different concentrations of atrazine, glyphosate or atrazine and glyphosate mixture. Forty-two eggs were randomly allocated to one of seven trays containing vermiculite treated distilled water (control group) or the following solutions: 2 or 200 µg L-1 of atrazine (groups A1 and A2 respectively); 65 or 6500 µg L-1 of glyphosate (groups G1 and G2 respectively); 2 µg L-1 and 65 µg L-1 or 200 µg L-1 and 6500 µg L-1 of atrazine and glyphosate mixture (groups AG1 and AG2 respectively). Three eggs per tray were randomly collected on days 30 and 50 of the incubation period. Embryos were submitted to soft tissue diaphanization and stained with Alizarin red S or Alcian blue for morphological analysis of bone and cartilage tissues; histological analysis was performed to confirm ossification changes. Findings were compared between groups. Morphological changes were limited to sclerotic ring features and number of ribs. Malformations rates differed significantly (p < 0.05) between embryos in the control and treated groups A2, AG1 and AG2. Concurrent exposure to atrazine and glyphosate did not affect the presence or severity of embryonic malformations and was not associated with appendicular skeleton changes in P. unifilis embryos. However, further studies focusing on the axial skeleton with particular emphasis on rib abnormalities are warranted.


Assuntos
Atrazina/toxicidade , Glicina/análogos & derivados , Óvulo/efeitos dos fármacos , Praguicidas/toxicidade , Testes de Toxicidade , Animais , Atrazina/análise , Desenvolvimento Ósseo , Osso e Ossos/química , Cartilagem , Ovos , Glicina/toxicidade , Osteogênese , Tartarugas
7.
Ecotoxicol Environ Saf ; 182: 109415, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299471

RESUMO

Erythromycin (ERY), azithromycin (AZI) and telithromycin (TEL) are widely-used macrolide antibiotics that are frequently detected in various water environments, including resource water and drinking water. In the performed chlorination disinfection process, at least 10, 20 and 200 new disinfection byproducts of ERY, AZI and TEL, respectively, were observed (the mixtures of the disinfection byproducts of ERY, AZI and TEL were named ERY-M, AZI-M and TEL-M, respectively). There is limited information available regarding their comparative toxicities, and their potential health risks are still unknown. In this study, the Jurkat cell line was used to compare the toxicities of the disinfection byproduct mixtures and their precursor compounds. The cell viability results indicated that the toxicity of ERY-M may not be enhanced after disinfection by chlorination. In contrast, at the same concentrations, AZI-M and TEL-M induced more significant inhibitory effects on cell viability than their parent compounds. Additionally, the total antioxidant capacity (T-AOC) and cell cytokine release (including interleukin-2, interleukin-8 and tumor necrosis factor-α) analyses of AZI-M and TEL-M further verified these results. Our findings demonstrate that the cytotoxicity of AZI and TEL was enhanced during the chlorination disinfection process. This investigation will provide substantial new details related to the toxicity of the mixed disinfection byproducts (DBPs) of ERY, AZI and TEL generated in the chlorination disinfection process.


Assuntos
Antibacterianos/toxicidade , Desinfetantes/toxicidade , Antibacterianos/análise , Desinfetantes/análise , Desinfecção/métodos , Água Potável/análise , Eritromicina/análise , Halogenação , Cetolídeos , Testes de Toxicidade , Poluentes Químicos da Água/análise , Purificação da Água/métodos
8.
Ecotoxicol Environ Saf ; 182: 109420, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299472

RESUMO

Mancozeb (MZ), chlorothalonil (CT), and thiophanate methyl (TM) are pesticides commonly used in agriculture due to their efficacy, low acute toxicity to mammals, and short environmental persistence. Although the toxic effects of these pesticides have been previously reported, studies regarding their influence on the immune system are limited. As such, this study focused on the immunomodulatory effect of MZ, CT, and TM pesticides on macrophage cells. RAW 264.7 cells were exposed to a range of concentrations (0.1-100 µg/mL) of these pesticides. CT exposure promoted an increase in reactive oxygen species (ROS) and nitric oxide (NO) levels. The MTT and ds-DNA assay results demonstrated that MZ, CT, and TM exposure induced macrophage proliferation. Moreover, MZ, CT, and TM promoted cell cycle arrest at S phase, strongly suggesting macrophage proliferation. The levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ) and caspases (caspase 1, 3, and 8) in macrophages exposed to MZ, CT, and TM pesticides increased, whereas the anti-inflammatory cytokine levels decreased. These results suggest that MZ, CT, and TM exert an immunomodulatory effect on the immune system, inducing macrophage activation and enhancing the inflammatory response.


Assuntos
Praguicidas/toxicidade , Animais , Citocinas/metabolismo , Imunomodulação , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Maneb/toxicidade , Óxido Nítrico/metabolismo , Nitrilos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Tiofanato/toxicidade , Testes de Toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Zineb/toxicidade
9.
J Environ Sci Health B ; 54(7): 539-548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31264931

RESUMO

Glyphosate (GLP) currently is one of the most widely used herbicides worldwide. The persistence of GLP and its major metabolite, aminomethylphosphonic acid (AMPA) in the environment has been described by other authors. This study was aimed at comparing the GLP and AMPA behavior in sandy and loamy sand soils after spiking with enhanced (445 µg g-1) concentrations of GLP in herbicide KLINIK® (Nufarm, Austria) and bioaugmentation followed by 40 days weathering and a consistent three-stage leaching in a laboratory column experiment. Soil samples were obtained from mineral topsoil (0-10 cm) within former agricultural lands where soil parent material was formed by glacigenic deposits. The total amount of GLP and AMPA collected during three leaching stages was significantly (p<.05) higher from columns with sandy soil, compared to loamy sand soil. Bioaugmentation resulted in considerably lower concentrations of AMPA in leachates, especially in the sets with sandy soil (p=.01). Leachates were tested using FTIR spectroscopy and Daphnia magna. Statistical analysis of the changes in Ntot, Ctot, K+, Mg2+, Al3+, Ca2+, Mn2+ and Fe3+ concentrations in soils after the leaching experiment revealed that the loamy sand soil was likely to be more sensitive to the addition of GLP and bioaugmentation than sandy soil.


Assuntos
Glicina/análogos & derivados , Poluentes do Solo/análise , Solo/química , Agricultura , Animais , Daphnia/efeitos dos fármacos , Glicina/análise , Glicina/química , Glicina/toxicidade , Herbicidas/análise , Herbicidas/química , Isoxazóis/análise , Compostos Organofosforados/análise , Compostos Organofosforados/química , Poluentes do Solo/química , Poluentes do Solo/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tetrazóis/análise , Testes de Toxicidade
10.
J Environ Radioact ; 208-209: 106011, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31288125

RESUMO

Thorium has gained notoriety in recent years, as a potential source of nuclear energy, substituting uranium in power plants. Monazite is an important source of thorium, as well of uranium and rare earths elements. Workers involved in the extraction and manipulation of this mineral are occupationally exposed to a range of metal mixtures containing thorium and to ionizing radiation. As an osteotropic substance, thorium is mostly deposited in bone tissue and may interfere in cellular radiosensitivity. A human osteoblast cell line was used to evaluate the effects of thorium (Th), cerium (Ce) and lanthanum (La) on cell radiosensivity, using proliferation as indicator. Assays were performed using cell cultures exposed to metals alone and metals combined with ionizing radiation. No stimulus of proliferation was observed when samples were exposed to metals or radiation alone. On the other hand, the metals were able to influence cell radiosensivity, in a concentration-dependent manner when metals and radiation were applied simultaneously. Samples irradiated and exposed to metals combinations revealed an interaction between them in all the tested arrangements (Th-Ce, Th-La, Th-Ce-La). All interactions proved to be of the antagonist type relative to the proliferation indicator, with a higher degree seen for the Th-Ce association. Such results showed the possibility that metal mixtures together with radiation may produce combined effects on osteoblasts, through modifications on the degree of radiosensivity. The results indicate the possibility of an enhancement in occupational risk for workers that manipulate monazite byproducts. Thus, the development of risk assessment models that include the evaluation of mixtures and their cytotoxic and radiotoxic effects on tissues and organs must be highlighted.


Assuntos
Cério/toxicidade , Lantânio/toxicidade , Tório/toxicidade , Linhagem Celular , Humanos , Osteoblastos , Testes de Toxicidade
11.
Toxicol Lett ; 314: 1-9, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295537

RESUMO

Oral administration is the preferred route of exposure for non-volatile chemicals with potential environmental exposures. For metal salts, systemic doses in such toxicity testing are often low due to limited oral bioavailability. Issues arising from the low bioavailability for toxicity testing and risk characterization are illustrated using aluminum (Al) salts as example. Al-cations have an oral bioavailability of below 1% and applicable doses are limited resulting in low systemic doses. Consequently, the low systemic doses are insufficient to induce clear adverse effects that may serve as points of departure for risk characterization.


Assuntos
Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/toxicidade , Testes de Toxicidade/métodos , Administração Oral , Compostos de Alumínio/farmacocinética , Animais , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Humanos , Reprodutibilidade dos Testes , Medição de Risco , Toxicocinética
13.
Environ Monit Assess ; 191(8): 478, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263965

RESUMO

Carwash effluents contain potentially toxic chemical and microbiological pollutants which may pose public health and ecotoxicological threats if directly discharged into surface waters. This work was aimed at determining the microbiological, physicochemical, and toxicological parameters of carwash effluents. Toxicity assays were determined using whole effluent toxicity (WET) using Danio rerio and Daphnia pulex. For microbiological analysis, sample aliquots were spread plated onto R2A Agar for the isolation of heterotrophic bacteria followed by DNA extraction from axenic cultures for sequencing analysis. The pH of effluent samples lay in the alkaline range, and ranged from pH 7 to pH 10. Sample salinity ranged from 0.2 to 0.3 g/Kg. Electrical conductivity values ranged from 274 to 554 µS/cm. Concentrations of Co, Pb, and Ni were < 1 mg/L in all samples while the concentrations of Cu ranged from 0.94 to 3.8 mg/L and Zn from 1.15 to 3 mg/L. Oil and grease concentrations ranged from 5 to 24 mg/L. The concentrations of TPH-GRO were low at < 1 mg/L in all samples. All the carwash effluents were categorised as acutely toxic, with ≥ 75% mortality recorded for both test organisms within the first 24 h of exposure to the test solutions. Heterotrophic bacteria counts ranged from 2800 to 4600 CFU/100 ml. Sequencing analysis revealed that 57% of the isolates were closely related to Aeromonas species, with 43% closely related to Pseudomonas species. We conclude that carwash effluents are veritable sources of microbiological contaminants and potentially toxic chemical pollutants of public health and ecotoxicological concern.


Assuntos
Monitoramento Ambiental , Veículos Automotores , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Bactérias , Daphnia , Ecotoxicologia , Testes de Toxicidade , Microbiologia da Água , Peixe-Zebra
14.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2131-2138, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355572

RESUMO

The dose-toxicity-effect relationship between licorice combined with rhubarb in purgation was studied. A total of 108 ICR mice were divided into control group,model group,positive group,low,medium and high-dose rhubarb groups,and low,medium and high-dose rhubarb-liquorice decoction group. After 6 days of continuous administration of loperamide hydrochloride,the constipation model of mice was replicated,and each group was given lactulose,different doses of rhubarb and rhubarb-liquorice decoction for 14 days. After administration,the defecation characteristics,blood biochemistry,liver,kidney and colon pathological changes in each group were compared. Based on the objective weight given by factor analysis,the dose-toxicity-effect relationship was comprehensively analyzed by multi-index scoring method. Two common factors were extracted by factor analysis,representing effect and toxicity respectively. The results showed that rhubarb could exert a diarrhea effect at the dosage of 1/2,2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,increase the defecation volume and the intestinal tract propulsion rate,reduce the time of anal and the oral transmission,and increase the water content of feces. The combination with licorice could alleviate its diarrhea effect,especially at the dosage of 1/2 times of the high limit set forth in the Chinese Pharmacopoeia. However,rhubarb showed obvious hepatic and colon toxicities at the dosage of 2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,and the combination with licorice could significantly reduce its toxicity. It shows that licorice has a " mediating" effect on rhubarb by alleviating the purgation property and reducing the toxicity.


Assuntos
Catárticos/farmacologia , Glycyrrhiza/química , Extratos Vegetais/farmacologia , Rheum/química , Animais , Colo , Relação Dose-Resposta a Droga , Rim , Fígado , Camundongos , Camundongos Endogâmicos ICR , Testes de Toxicidade
15.
J Environ Sci (China) ; 84: 97-111, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284920

RESUMO

Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants. Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in literature. However, the reported degradation intermediates are normally inconsistent. This issue is especially important for the degradation of toxic compounds because intermediates may be more toxic than their parent compounds and understanding the reason is necessary if appropriate catalysts are to be designed. This work systematically compares the photocatalytic degradation of diuron, a toxic recalcitrant herbicide, on two forms of zinc oxide (ZnO), i.e., conventional particles with zinc- and oxygen-terminated polar surfaces as the dominating planes, and nanorods with mixed-terminated nonpolar surfaces. Experimental and theoretical results indicate that both the rate of reaction and the degradation pathway depend on the adsorption configuration of diuron onto the surface. Diuron molecules adsorb in different alignments on the two surfaces, contributing to the formation of different degradation intermediates. Both the aliphatic and aromatic sides of diuron adsorb on the polar surfaces simultaneously, leading to an attack by hydroxyl radicals from both ends. On the other hand, on the mixed-terminated surface, only the aliphatic part adsorbs and is degraded. The exposed surface is therefore the key factor controlling the degradation pathway. For diuron degradation on ZnO, a catalyst confined to mixed-terminated surfaces, i.e., ZnO nanorods, is more desirable, as it avoids the formation of intermediates with potent phytotoxicity and cytogenotoxicity.


Assuntos
Diurona/química , Fotólise , Poluentes Químicos da Água/química , Óxido de Zinco/química , Adsorção , Catálise , Cinética , Testes de Toxicidade , Vigna
16.
Environ Monit Assess ; 191(8): 513, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31346830

RESUMO

In this study, a method was developed to evaluate the degradation of haloacetic acids (HAAs) in water by a heterogenous Fenton-like process catalyzed by cobalt-doped magnetite nanoparticles (Fe3 - xCoxO4), extraction of the contaminants by liquid-liquid extraction (LLE), and analysis by gas chromatography-mass spectrometry (GC-MS). The developed method was efficient in the degradation of HAAs, with the following degradation values: 63%, 62%, 30%, 39%, 37%, 50%, 84%, 41%, and 79% for monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, trichloroacetic acid, bromochloroacetic acid, dibromoacetic acid, bromodichloroacetic acid, dibromochloroacetic acid, and tribromoacetic acid compounds, respectively. Through the application of the Allium cepa test, the cytotoxicity, genotoxicity, and mutagenicity of HAAs were evaluated. The results confirm its genotoxic and mutagenic effects on Allium cepa meristematic cells. Through this study, it was possible to verify the effectiveness of the developed method and its potential as a proposal for environmental remediation.


Assuntos
Bioensaio , Cloroacetatos/toxicidade , Mutagênicos/toxicidade , Testes de Toxicidade , Acetatos/toxicidade , Ácido Acético , Dano ao DNA , Ácido Dicloroacético/toxicidade , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Bromados/toxicidade , Ácido Tricloroacético/toxicidade , Água/análise , Abastecimento de Água
17.
Arch Insect Biochem Physiol ; 102(1): e21596, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31270854

RESUMO

ß-Asarone is the predominant component of the essential oil of rhizomes of Acorus calamus Linn ( Sweet flag). Although rhizome extracts from this plant have long been used for insect pest control, their cytotoxic effects on insect cells are not well understood. In this study, we evaluated the potency of ß-asarone as a natural insecticide by using a Spodoptera frugiperda cell line (Sf9). To assess the cytotoxic effects of ß-asarone on Sf9 cells, we observed morphologic changes in treated cells and performed a cell proliferation assay and a DNA fragmentation assay. After 24 and 48 h of treatment with ß-asarone, the proliferation of the Sf9 cells was inhibited in a dose-dependent manner, with IC50 values of 0.558 mg/ml at 24 h and 0.253 mg/ml at 48 h. Morphologic changes in ß-asarone-treated cells were typical of apoptosis and included loss of adhesion, cell shrinkage, and small apoptotic bodies. The DNA laddering present in ß-asarone-treated SF9 cells and annexin V assay confirmed that this compound can induce apoptosis in insect cells. Together, these findings suggest that apoptosis induction may be one mechanism through which ß-asarone inhibits the proliferation of insect cells and thus exerts insecticidal effects.


Assuntos
Anisóis/toxicidade , Acorus , Animais , Apoptose , Fragmentação do DNA , Células Sf9 , Spodoptera , Testes de Toxicidade
18.
Environ Sci Pollut Res Int ; 26(23): 23491-23504, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201698

RESUMO

This study was conducted to investigate the effects of maternal exposure to bisphenol A (BPA) on testis development of F1 male mice. The BPA exposure model of pregnant mice was prepared by intragastric administration of BPA at the doses of 0, 2.5, 5, 10, 20, and 40 mg/kg/day at gestation day (GD) 0.5-17.5. The testis index of the offspring mice was calculated at postnatal day (PND) 21 and PND 56. The results showed that maternal exposure to 20 mg/kg BPA during pregnancy significantly increased the testicular index of F1 males at PND 21, and 40 mg/kg BPA significantly decreased the testicular index of F1 males at PND 56 (P < 0.01). BPA significantly reduced serum testosterone (T) and estradiol (E2) levels, and improved testicular ERα and ERß levels in F1 males at both PND 21 and PND 56. BPA exposure also upregulated transcription of testicular Dnmt1 and inhibited the transcription of testicular Dnmt3A and Dnmt3B in F1 mice at PND 21. BPA reduced the transcriptional level of testicular DNA methyltransferase (Dnmt), increased the expression of testicular caspase-7, caspase-9, and bax, and decreased the expression of bcl-2 in F1 mice at PND 56. Consistent with that, BPA improved the apoptosis rate in the testis at PND 56 (P < 0.01 or P < 0.05). Our study indicates that BPA disrupts the secretion of testosterone, estradiol, and estrogen receptors by interfering with the transcription of testicular DNA methyltransferase (Dnmt) in offspring males, which damages testicular tissues and affects the potential reproductive function.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Testículo/crescimento & desenvolvimento , Animais , DNA (Citosina-5-)-Metiltransferases , Estradiol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Masculino , Exposição Materna , Camundongos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Proteínas Proto-Oncogênicas c-bcl-2 , Receptores Estrogênicos/metabolismo , Diferenciação Sexual , Testículo/efeitos dos fármacos , Testosterona/sangue , Testes de Toxicidade
19.
Ecotoxicol Environ Saf ; 182: 109369, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31238115

RESUMO

Growth and developmental changes in plants induced by pharmaceuticals reflect changes in processes at the cellular and subcellular levels. Due to their growth and cellular characteristics, plant cell suspension cultures can be a suitable model for assessing toxicity. In this study, 10-1000 µg/L of the non-steroidal anti-inflammatory drug diclofenac (DCF) decreased the viability of Nicotiana tabacum BY-2 cells after 24 h of treatment. Further, 0.1-10 mg/L DCF diminished the density of the cell suspension by 9-46% after 96 h of treatment, but at 1 and 10 µg/L, DCF increased the density by 13% and 5%, respectively, after 120 h. These changes were accompanied by increased production of total reactive oxygen species (ROS) and mitochondrial superoxide (up to 17-fold and 5-fold, respectively), and a decrease in the mitochondrial membrane potential (by ∼64%) especially at 1000 µg/L DCF. The increased ROS production was accompanied by decrease in level of reactive nitrogen species (RNS; by 36%) and total thiols (by 61%). Damage to BY-2 cells was evidenced by accumulation of neutral red in acidic compartments (up to 10-fold at 1000 µg/L DCF), and increase of autophagic vacuole formation (up to 8-fold at 1000 µg/L DCF). Furthermore, irregular or stretched nuclei were observed in nearly 27% and 50% of cells at 100 and 1000 µg/L DCF, respectively. Highest levels of chromatin condensation (11% of cells) and apoptotic DNA fragmentation (7%) were found at 10 µg/L DCF. The results revealed a significant effect of DCF on BY-2 cells after 24 h of exposure. Changes in the growth and viability parameters were indisputably related to ROS and RNS production, changes in mitochondrial function, and possible activation of processes leading to cell death.


Assuntos
Anti-Inflamatórios não Esteroides/toxicidade , Diclofenaco/toxicidade , Testes de Toxicidade/métodos , Mitocôndrias/metabolismo , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio/metabolismo , Superóxidos , Suspensões , Tabaco/metabolismo
20.
Environ Sci Pollut Res Int ; 26(22): 22562-22574, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165450

RESUMO

Zingerone (ZO), one of the active components of ginger (Zingiber officinale), is a phenolic alkanone with antioxidant, antiapoptotic, and anti-inflammatory properties. Cisplatin (CP) is a widely used chemotherapeutic drug for solid tumors, but its therapeutic use is limited due to dose-dependent nephrotoxicity. In the present study, we investigated the ameliorative effect of ZO against CP-induced nephrotoxicity. Intraperitoneal administration of single-dose CP (7 mg/kg body weight) on the first day enhanced kidney lipid peroxidation and reduced antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH). CP increased serum urea and creatinine levels and disrupted histological integrity while causing a decrease aquaporin 1 (AQP1) level in the kidney tissues. CP induced inflammatory responses by elevating the levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-33 (IL-33) and nuclear factor kappa B (NF-κB), and activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, it also caused oxidative DNA damage and activation of apoptotic pathway by increasing of 8-hydroxy-2'-deoxyguanosine (8-OHdG), p53, cysteine aspartate-specific protease-3 (caspase-3), and Bcl-2-associated x protein (bax) while decreasing B cell lymphoma-2 (Bcl-2). However, treatment with ZO at a dose of 25 and 50 mg/kg b.wt. for 7 days significantly decreased oxidative stress, apoptosis, inflammation, and histopathological alterations while increased AQP1 levels in the kidney tissue. The results of the current study suggested that ZO as an effective natural product attenuates CP-induced nephrotoxicity.


Assuntos
Antioxidantes/metabolismo , Cisplatino/toxicidade , Guaiacol/análogos & derivados , Rim/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Autofagia , Nitrogênio da Ureia Sanguínea , Catalase/metabolismo , Dano ao DNA , Desoxiguanosina/análogos & derivados , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Guaiacol/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Rim/metabolismo , Peroxidação de Lipídeos , Masculino , NF-kappa B/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos , Superóxido Dismutase/metabolismo , Testes de Toxicidade , Fator de Necrose Tumoral alfa/metabolismo
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