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1.
Chemosphere ; 254: 126794, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957267

RESUMO

Present study carried out pot experiments and evaluated effects of single and binary mixture of nanoparticles (exposed via sludge as soil conditioner) on spinach plant. Exposure of Ag2O nanoparticles (NPs) (1 and 10 mg/kg soil-sludge) did not show significant reduction in plant as compared to control. On the other hand, TiO2 NPs (exposed as single and in binary mixture) resulted in significant increase in root length (29% and 37%) and fresh weight (60% and 48%) at highest exposure concentration. Total chlorophyll content decreased for Ag2O and binary mixture (7% and 4%, respectively) and increased for TiO2 (5%) at 10 mg/kg soil-sludge. The toxic interaction between Ag2O and TiO2 NPs was additive at both exposure concentrations. Ag2O NPs had higher tendency of root surface adsorption than TiO2 NPs. Metal content in spinach leaves at highest exposure concentration was Ag: 2.6 ± 0.55 mg/g plant biomass(for Ag2O NPs) and 1.02 ± 0.32 mg/g plant biomass (for Ag2O + TiO2 NPs) and for Ti: 1.12 ± 0.78 (for TiO2 NPs) mg/g plant biomass and 0.58 ± 0.41 mg/g (for Ag2O + TiO2 NPs). The inadvertent ingestion of NPs- contaminated spinach resulted in projected daily intake (DI) of Ag and Ti for different age-mass classes (child to adult) exceeding the oral reference dose for toxicity during oral ingestion. In conclusion, we report no acute toxicity of single and binary mixture of NPs to spinach but significant accumulation of Ag and Ti metals in spinach leaves. There are high chances that ingestion of spinach grown in such environment might lead to human health risks.


Assuntos
Nanopartículas/toxicidade , Poluentes do Solo/toxicidade , Spinacia oleracea/efeitos dos fármacos , Biomassa , Clorofila , Humanos , Nanopartículas Metálicas/toxicidade , Metais/toxicidade , Nanopartículas/análise , Folhas de Planta/química , Esgotos , Solo , Poluentes do Solo/análise , Spinacia oleracea/crescimento & desenvolvimento , Titânio/farmacologia
2.
Bull Environ Contam Toxicol ; 105(4): 530-537, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32940716

RESUMO

An increase in the production and usage of gold nanoparticles (AuNPs) triggers the necessity to focus on their impact on ecosystems. Therefore, the purpose of this study was to investigate the acute toxicity of AuNPs and ionic gold (Au (III)) to organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (crustacean Daphnia magna, embryos of Danio rerio) and decomposers (bacteria Vibrio fischeri). The organisms were exposed according to a standardized protocol for each species and endpoints. The AuNPs (1.16 and 11.6 d.nm) were synthesized using citrate (CIT) and polyvinylpyrrolidone (PVP) as capping agents, respectively. It was found, that Au (III) was significantly more toxic than AuNPs PVP and AuNPs CIT. AuNPs showed significant toxicity only at high concentrations (mg/L), which are not environmentally relevant in the present time, but a cautious approach is advised, due to the possibility of interactions with other contaminants.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Araceae/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Ouro/toxicidade , Íons/toxicidade , Nanopartículas Metálicas/toxicidade , Peixe-Zebra , Animais , Organismos Aquáticos , Daphnia/embriologia , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Testes de Toxicidade Aguda
3.
Cent Eur J Public Health ; 28(3): 202-207, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32997476

RESUMO

OBJECTIVE: Nanomaterials consist of particles smaller than 100 nm - nanoparticles (NPs). Their nano dimensions allow them to penetrate through various membranes and enter into the bloodstream and disseminate into different body organs. Massive expansion of nanotechnologies together with production of new nanoparticles which have not yet been in contact with living organisms may pose a potential health problem. It is therefore necessary to investigate the health impact of NPs after experimental exposure. Comparison of the effect of TiO2 and NPs Fe3O4 in Wistar rats at time intervals 1, 7, 14 and 28 days was performed by studying the cytotoxic effect in the isolated inflammatory cells from bronchoalveolar lavage (BAL). METHODS: Wistar rats were intravenously (i.v.) given a suspension of NPs TiO2 or Fe3O4 (coated by sodium oleate) via the tail vein. After time intervals of 1, 7, 14 and 28 days, we sacrificed the animals under anaesthesia, performed BAL and isolated the cells. The number of animals in the individual groups was 7-8. We examined the differential count of BAL cells (alveolar macrophages - AM, polymorphonuclear leukocytes - PMN, lymphocytes - Ly); viability and phagocytic activity of AM; the proportion of immature and polynuclear cells and enzymes - cathepsin D - CAT D, lactate dehydrogenase - LDH and acid phosphatase - ACP. RESULTS: We found that TiO2 NPs are relatively inert - without induction of inflammatory and cytotoxic response. Exposure to nanoparticles Fe3O4 induced - under the same experimental conditions - in comparison with the control and TiO2 a more extensive inflammatory and cytotoxic response, albeit only at 1, 7 and 14 days after injection. CONCLUSIONS: The results suggest that TiO2 and Fe3O4 nanoparticles used in our study were transferred from the bloodstream to the respiratory tract, but this effect was not observed at 28 days after i.v. injection, probably due to their removal from the respiratory tract.


Assuntos
Óxido Ferroso-Férrico/toxicidade , Nanopartículas Metálicas/toxicidade , Doenças Respiratórias/induzido quimicamente , Titânio/toxicidade , Administração Intravenosa , Animais , Óxido Ferroso-Férrico/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Ratos , Ratos Wistar , Titânio/administração & dosagem
4.
Ecotoxicol Environ Saf ; 202: 110911, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800246

RESUMO

Applications of TiO2 nanoparticles (NPs) in food, personal care products and industries pose risks on human health, particularly on vulnerable populations including pregnant women and infants. Fetus, deficient in mature defense system, is more susceptible to NPs. Publications on the developmental toxicity of TiO2 NPs on the maternal-exposed progeny have emerged. This review presents the main exposure routes of TiO2 NPs during pregnancy, including skin penetration, ingestion and inhalation, followed by transport of TiO2 NPs to the placenta. Accumulation of TiO2 NPs in placenta may cause dysfunction in nutrient transfer. TiO2 NPs can be even transported to the fetus and generate toxicities, such as impairments of nervous and reproductive system, and failure in lung and cardiovascular development. The toxicities rely on the crystalline phase and concentrations, and the main mechanisms include the accumulation of excessive reactive oxygen species, DNA damage, and over-activation of signaling pathways such as MAPK which impairs neurotransmission. Finally, this review remarks on the significance for identifying TiO2 NPs dosage safe for both mother and fetus, and particular attention should be paid at TiO2 NPs concentrations safe for mother but toxic to fetus. Importantly, research on the epigenetic trans-generational inheritance of TiO2 NPs is urgently needed to provide insights for deciding the prospects of TiO2 NPs applications.


Assuntos
Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Animais , Feminino , Feto , Humanos , Nanopartículas/toxicidade , Organogênese , Placenta/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
5.
Aquat Toxicol ; 227: 105582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32823071

RESUMO

While it is likely that ENPs may occur together with other contaminants in nature, the combined effects of exposure to both ENPs and environmental contaminants are not studied sufficiently. In this study, we investigated the acute and sublethal toxicity of PVP coated silver nanoparticles (AgNP) and ionic silver (Ag+; administered as AgNO3) to the marine copepod Calanus finmarchicus. We further studied effects of single exposures to AgNPs (nominal concentrations: low 15 µg L-1 NPL, high 150 µg L-1 NPH) or Ag+ (60 µg L-1), and effects of co-exposure to AgNPs, Ag+ and the water-soluble fraction (WSF; 100 µg L-1) of a crude oil (AgNP + WSF; Ag++WSF). The gene expression and the activity of antioxidant defense enzymes SOD, CAT and GST, as well as the gene expression of HSP90 and CYP330A1 were determined as sublethal endpoints. Results show that Ag+ was more acutely toxic compared to AgNPs, with 96 h LC50 concentrations of 403 µg L-1 for AgNPs, and 147 µg L-1 for Ag+. Organismal uptake of Ag following exposure was similar for AgNP and Ag+, and was not significantly different when co-exposed to WSF. Exposure to AgNPs alone caused increases in gene expressions of GST and SOD, whereas WSF exposure caused an induction in SOD. Responses in enzyme activities were generally low, with significant effects observed only on SOD activity in NPL and WSF exposures and on GST activity in NPL and NPH exposures. Combined AgNP and WSF exposures caused slightly altered responses in expression of SOD, GST and CYP330A1 genes compared to the single exposures of either AgNPs or WSF. However, there was no clear pattern of cumulative effects caused by co-exposures of AgNPs and WSF. The present study indicates that the exposure to AgNPs, Ag+, and to a lesser degree WSF cause an oxidative stress response in C. finmarchicus, which was slightly, but mostly not significantly altered in combined exposures. This indicated that the combined effects between Ag and WSF are relatively limited, at least with regard to oxidative stress.


Assuntos
Copépodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Petróleo/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Copépodes/genética , Copépodes/metabolismo , Interações Medicamentosas , Expressão Gênica/efeitos dos fármacos , Íons , Nanopartículas Metálicas/química , Estresse Oxidativo/genética , Água do Mar/química , Prata/química , Solubilidade , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda , Poluentes Químicos da Água/química
6.
Ecotoxicol Environ Saf ; 204: 111104, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32791360

RESUMO

Since development of antioxidant defence system is high energy demanding event, innate defence system and stress tolerance of plant is strictly governed by plant age. This study is aimed towards evaluating variation of tolerance in germinating seeds and seedlings of Oryza sativa L. cv. Swarna against nano-scale zero valent iron (nZVI). A comparative study of several physiological and biochemical parameters have been carried out among 2 distinct plant groups, Group I treated with variable concentrations of nZVI (50, 100, 150 and 200 mg L-1) during germination and Group II treated with similar nZVI doses on 7th day after germination. Upon treatment with higher nZVI concentrations, Group I seedlings showed susceptibility towards oxidative stress while Group II seedlings showed tolerance against these higher doses of nZVI. Significant growth enhancement was observed upon treatment with 50-150 mg L-1 nZVI, since up-regulation of plant's endogenous antioxidant system protected relatively aged Group II seedlings from oxidative damages. Hierarchical clustering based on overall physiological, biochemical and stress parameters confirmed that in Group I seedlings 100-200 mg L-1 nZVI treatments were toxic where as in Group II seedlings 50-150 mg L-1 nZVI treatments showed growth promoting effects. This differential response is due to developmental stage related resistance in plants.


Assuntos
Germinação/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oryza/crescimento & desenvolvimento , Antioxidantes/metabolismo , Ferro/metabolismo , Oryza/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Plântula/efeitos dos fármacos , Sementes/metabolismo
7.
Ecotoxicol Environ Saf ; 204: 111070, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32763567

RESUMO

Silver nanoparticles (AgNPs) are widely used as antimicrobial agents and resulted in their accumulation in environment. The purpose of this study was to investigate the detailed molecular mechanisms underlying AgNP-induced lung cellular senescence which has been proposed as a pathogenic driver of chronic lung disease. Herein, we demonstrate that exposure to AgNPs elevates multiple senescence biomarkers in lung cells, with cell cycle arrest in the G2/M phase, and potently activates genes of the senescence-associated secretory phenotype (SASP) in human fetal lung fibroblast cell line MRC5. Fluorescence-based assay also reveals that apoptosis induced by AgNPs is associated with senescence. Furthermore, we show that AgNPs cause premature senescence through an increase in transcription factor nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX2) expression and over-production of prostaglandin E2 (PGE2) in lung cells. Inhibition of COX2 reduces AgNPs-induced senescence to a normal level. Moreover, AgNPs also induce upregulation of COX2 and accelerate lung cellular senescence in vivo and cause mild fibrosis in the lung tissue of mice. Taken together, our studies support a critical role of AgNPs in the induction of lung cellular senescence via the upregulation of the COX2/PGE2 intracrine pathway, and suggest the adverse effects to the human respiratory system.


Assuntos
Senescência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Prata/metabolismo
8.
J Toxicol Sci ; 45(8): 411-422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32741894

RESUMO

Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in photoelectric and catalytic applications. However, their exposure and reproductive toxicity is unknown. In this study, the effect of the intragastric administration of two different-sized La2O3 particles in the testes of mice for 60 days was investigated. Although the body weight of mice treated or not treated with La2O3 NPs was not different and La2O3 NPs were distributed in the organs including the testis, liver, kidney, spleen, heart and brain. La2O3 NPs accumulate more than micro-sized La2O3 (MPs) in mice testes. The histopathological evaluation showed that moderate reproductive toxicity induced by La2O3 NPs in the testicle tissues. Furthermore, increased MDA, 8-OHdG levels and decreased SOD activities were detected in the La2O3 NP-treated groups. Moreover, qRT-PCR and western blotting data indicated that La2O3 NPs affecting the blood-testis barrier (BTB)-related genes in mice testes. Taken together, these findings suggested that La2O3 NPs activated inflammation responses and cross the BTB in the murine testes. This study provided useful information for risk analysis and regulation of La2O3 NPs by administrative agencies.


Assuntos
Lantânio/administração & dosagem , Lantânio/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos/administração & dosagem , Óxidos/toxicidade , Tamanho da Partícula , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Animais , Barreira Hematotesticular/metabolismo , Desoxiadenosinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação , Lantânio/metabolismo , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/administração & dosagem , Camundongos , Óxidos/metabolismo , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Distribuição Tecidual
9.
Int J Nanomedicine ; 15: 4091-4104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606666

RESUMO

Introduction: Humans are intentionally exposed to gold nanoparticles (AuNPs) where they are used in variety of biomedical applications as imaging and drug delivery agents as well as diagnostic and therapeutic agents currently in clinic and in a variety of upcoming clinical trials. Consequently, it is critical that we gain a better understanding of how physiochemical properties such as size, shape, and surface chemistry drive cellular uptake and AuNP toxicity in vivo. Understanding and being able to manipulate these physiochemical properties will allow for the production of safer and more efficacious use of AuNPs in biomedical applications. Methods and Materials: Here, AuNPs of three sizes, 5 nm, 10 nm, and 20 nm, were coated with a lipid bilayer composed of sodium oleate, hydrogenated phosphatidylcholine, and hexanethiol. To understand how the physical features of AuNPs influence uptake through cellular membranes, sum frequency generation (SFG) was utilized to assess the interactions of the AuNPs with a biomimetic lipid monolayer composed of a deuterated phospholipid 1.2-dipalmitoyl-d62-sn-glycero-3-phosphocholine (dDPPC). Results and Discussion: SFG measurements showed that 5 nm and 10 nm AuNPs are able to phase into the lipid monolayer with very little energetic cost, whereas, the 20 nm AuNPs warped the membrane conforming it to the curvature of hybrid lipid-coated AuNPs. Toxicity of the AuNPs were assessed in vivo to determine how AuNP curvature and uptake influence cell health. In contrast, in vivo toxicity tested in embryonic zebrafish showed rapid toxicity of the 5 nm AuNPs, with significant 24 hpf mortality occurring at concentrations ≥20 mg/L, whereas the 10 nm and 20 nm AuNPs showed no significant mortality throughout the five-day experiment. Conclusion: By combining information from membrane models using SFG spectroscopy with in vivo toxicity studies, a better mechanistic understanding of how nanoparticles (NPs) interact with membranes is developed to understand how the physiochemical features of AuNPs drive nanoparticle-membrane interactions, cellular uptake, and toxicity.


Assuntos
Membrana Celular/química , Ouro/toxicidade , Lipídeos/química , Membranas Artificiais , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Testes de Toxicidade , Animais , Embrião não Mamífero/anormalidades , Embrião não Mamífero/efeitos dos fármacos , Humanos , Espectrofotometria Ultravioleta , Análise Espectral , Peixe-Zebra/embriologia
10.
Int J Nanomedicine ; 15: 4441-4452, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606688

RESUMO

Purpose: The present study focuses on threshold levels for cytotoxicity after long-term and repetitive exposure for HUVEC as a model for the specific microvascular endothelial system. Furthermore, possible genotoxic effects and functional impairment caused by ZnO NPs in HUVEC are elucidated. Methods: Thresholds for cytotoxic effects are determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Annexin V assay. To demonstrate DNA damage, single-cell microgel electrophoresis (comet) assay is performed after exposure to sub-cytotoxic concentrations of ZnO NPs. The proliferation assay, dot blot assay and capillary tube formation assay are also carried out to analyze functional impairment. Results: NPs showed to be spherical in shape with an average size of 45-55 nm. Long-term exposure as well as repetitive exposure with ZnO NPs exceeding 25 µg/mL lead to decreased viability in HUVEC. In addition, DNA damage was indicated by the comet assay after long-term and repetitive exposure. Twenty-four hours after long-term exposure, the proliferation assay does not show any difference between negative control and exposed cells. Forty-eight hours after exposure, HUVEC show an inverse concentration-related ability to proliferate. The dot blot assay provides evidence that ZnO NPs lead to a decreased release of VEGF, while capillary tube formation assay shows restriction in the ability of HUVEC to build tubes and meshes as a first step in angiogenesis. Conclusion: Sub-cytotoxic concentrations of ZnO NPs lead to DNA damage and functional impairment in HUVEC. Based on these data, ZnO NPs may affect neo-angiogenesis. Further investigation based on tissue cultures is required to elucidate the impact of ZnO NPs on human cell systems.


Assuntos
Dano ao DNA , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Óxido de Zinco/toxicidade , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neovascularização Fisiológica/efeitos dos fármacos
11.
Chemosphere ; 259: 127481, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32650163

RESUMO

Zinc Oxide nanoparticles (ZnO NPs) has been heavily used in the industry, and increasing concerns on the ecotoxicity has arisen due to the risk of release into the environment. In this work, silkworm was used here as a model organism to study the toxicity of ZnO NPs, due to the presence of a conserved immune response as well as a pharmacokinetics similar to mammals. Zn accumulation, biodistribution and toxicity in silkworms were monitored at different time points after a subcutaneous injection. The highest cumulative content of ZnO NPs was detected in the midgut. The results of catalytic activity studies confirmed that the antioxidant enzymes (SOD, CAT, GSH-PX) in midgut cells were expressed in response to ZnO NPs. The expression of genes (Dronc and Caspase-1) related to apoptosis was increased, while the Trt gene was down-regulated. A possible mechanism was proposed for toxicity of ZnO NPs to silkworms.


Assuntos
Bombyx/fisiologia , Nanopartículas Metálicas/toxicidade , Óxido de Zinco/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose , Bombyx/metabolismo , Nanopartículas , Distribuição Tecidual , Testes de Toxicidade Aguda
12.
Environ Sci Pollut Res Int ; 27(31): 38871-38880, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32638302

RESUMO

The present study was designed to investigate the nephrotoxicity of silver nanoparticles (AgNPs; 80 mg/kg; > 100 nm) and to evaluate the protective effect exercised by Beta vulgaris (beetroot) juice (RBR; 200 mg/kg) on male rats' kidney. Serum-specific parameters (urea, creatinine, electrolytes and histopathology of kidney tissue) were examined to assess the AgNPs nephrotoxicity effect. Moreover, this study analysed oxidative stress (lipid peroxidation, glutathione, superoxide dismutase and catalase) and anti-apoptotic markers (Bcl-2). AgNPs intoxication increased kidney function marker levels and lipid peroxidation and decreased the glutathione, superoxide dismutase and catalase activities in kidney tissue. Additionally, Bcl-2 expression was downregulated following AgNPs intoxication. Moreover, AgNPs induced a significant increase in renal DNA damage displayed as an elevation in tail length, tail DNA percentage and tail moment. Interestingly, RBR post-treatment restored the biochemical and histological alterations induced by AgNPs exposure, reflecting its nephroprotective effect. Collectively, the present data suggest that RBR could be used as a potential therapeutic intervention to prevent AgNPs-induced nephrotoxicity.


Assuntos
Beta vulgaris , Nanopartículas Metálicas/toxicidade , Animais , Antioxidantes , Rim , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo , Ratos , Prata/toxicidade , Superóxido Dismutase
13.
Bull Environ Contam Toxicol ; 105(2): 244-249, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32556691

RESUMO

The aim of the study was to assess the effects of silver nanoparticles (AgNPs1 = 2.7 d·nm, AgNPs2 = 6.5 d·nm) and silver nitrate (AgNO3) on Enchytraeus crypticus and Folsomia candida using toxicity tests (OECD Guideline 220, 232). A 28-day chronic toxicity study was performed to evaluate the reproduction and mortality rate. E. crypticus reproduction was more sensitive to AgNO3 with a 28dEC50 of 86.40 (62.52-119.4) mg·kg-1 dry weight (d.w.) compared to AgNPs1 (28dEC50 = 119.3 (60.4-235.6) mg·kg-1 d.w). Similarly, the reproduction of F. candida was inhibited the most by AgNO3 with a 28dEC50 of 126.2 (104.2-152.9) mg·kg-1 d.w. followed by AgNPs1 (28dEC50 = 158.7 (64.05-393.2) mg·kg-1 d.w.) and AgNPs2 (28dEC50 = 206.4 (181.9-234.1) mg·kg-1 d.w.). No mortalities were observed for tested soil invertebrates exposed to AgNPs at concentrations up to 166 mg·kg-1 d.w. of AgNPs1 and 300 mg·kg-1 d.w. of AgNPs2, respectively. It was found that silver ions are more toxic in comparison with AgNPs.


Assuntos
Artrópodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Nitrato de Prata/toxicidade , Prata/toxicidade , Poluentes do Solo/toxicidade , Animais , Íons , Nanopartículas Metálicas/química , Reprodução/efeitos dos fármacos , Prata/química , Solo/química , Solo/normas , Poluentes do Solo/química , Testes de Toxicidade Crônica
14.
Biol Res ; 53(1): 26, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513271

RESUMO

BACKGROUND: There is an emerging field to put into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. RESULTS: We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. CONCLUSIONS: Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium's oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.


Assuntos
Escherichia coli/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
15.
Toxicol Lett ; 331: 218-226, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32562635

RESUMO

INTRODUCTION: The benchmark dose (BMD) is a dose that produces a predetermined change in the response rate of an adverse effect. This approach is increasingly utilized to analyze quantitative dose-response relationships. To proof this concept, statistical analysis was compared with the BMD approach in order to rank the sensitivity as well as the toxicity and to describe the mode of action. METHODS: Bronchial (BEAS-2B) and alveolar epithelial cells (A549) were exposed to a wide concentration range (0.4-100 µg/mL) of five metal oxide nanoparticles (CeO2, CuO, TiO2, ZnO, ZrO2). Eight toxicity endpoints were determined representing integrity of lysosomal and cell membrane, oxidative stress level, glutathione based detoxification (glutathione S-transferase), oxidative metabolism (cytochrome P450), alteration of the mitochondrial membrane potential, alteration of phase II antioxidative enzyme (NAD(P)H:quinone oxidoreductase), and de novo DNA synthesis. RESULTS: Based on the BMD calculated for the most sensitive test, the toxicity decreased in the following order: ZnO > CuO > TiO2>ZrO2>CeO2 in BEAS-2B. Both statistical evaluation methods revealed a higher sensitivity of BEAS-2B cells. The BMD-derived mode of action for CuO confirmed the existing hypotheses and provided insights into less known mechanisms. CONCLUSION: The findings proofed that BMD analysis is an effective tool to evaluate different aspects of risk assessment.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Células A549 , Benchmarking , Brônquios/citologia , Relação Dose-Resposta a Droga , Determinação de Ponto Final , Humanos , Pulmão/citologia , Óxidos , Medição de Risco
16.
Int J Nanomedicine ; 15: 3827-3842, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581533

RESUMO

Introduction: Copper oxide nanoparticles (CuO-NPs) are widely used as feed additives for livestock and poultry and implicated in many biomedical applications; however, overload of copper NPs induces various toxicological changes and dysfunction of animal's organs. Thus, this study was designed to evaluate the comparative toxicological effects of biologically and chemically synthesized CuO-NPs on mice. Methods: Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) were used to characterize the sizes, shapes and functional groups of CuO-NPs. Forty-five mice were randomly allocated into three groups. Control group received distilled water. The second group was administered a single dose of biologically synthesized CuO-NPs (500 mg/kg bw) orally. The third group was administered a single dose of chemically synthesized CuO-NPs (500 mg/kg bw) orally. Results: TEM revealed that biologically synthesized NPs were spherical in shape, whereas chemically synthesized NPs were spherical or elongated in shape. XRD showed that the size of biologically synthesized NPs ranged from 4.14 to 12.82 nm and that of chemically synthesized NPs ranged from 4.06 to 26.82 nm. FT-IR spectroscopy indicated that the peaks appeared between 779 cm-1 and 425 cm-1 in biologically synthesized NPs and between 858 cm-1 and 524 cm-1 in chemically synthesized NPs were for Cu-O nanostructure. Four mice died due to administration of biologically synthesized CuO-NPs. Both biologically and chemically synthesized CuO-NPs induced leukocytosis, elevated serum activities of alanine aminotransferase and aspartate aminotransferase and serum levels of urea and creatinine and increased P53 mRNA and caspase-3 protein expressions in hepatic tissues. Moreover, CuO-NPs induced degenerative and necrotized changes in hepatic, renal and splenic tissues. Biochemical, apoptotic and pathological changes were more serious in mice administered with biologically synthesized CuO-NPs. Conclusion: This study indicated that a high dose of biologically and chemically synthesized CuO-NPs induced adverse effects on hepatic, renal and splenic tissues. At the same dose level, the biologically synthesized CuO-NPs evoked more potent toxic effects than the chemically synthesized CuO-NPs.


Assuntos
Cobre/toxicidade , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Administração Oral , Animais , Caspase 3/metabolismo , Cobre/administração & dosagem , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Nanopartículas Metálicas/administração & dosagem , Camundongos , Microscopia Eletrônica de Transmissão , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Baço/efeitos dos fármacos , Baço/patologia , Ulva/metabolismo , Difração de Raios X
17.
Int J Nanomedicine ; 15: 3471-3482, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547008

RESUMO

Introduction: Nanoparticles are at the forefront of rapidly developing nanotechnology and have gained much attention for their application as an effective drug delivery system and as a mediated therapeutic agent for cancer. However, the cytotoxicity of nanoparticles is still relatively unknown and, therefore, additional study is required in order to elucidate the potential toxicity of these nanoparticles on cells. Materials and Methods: Thus, the following work aimed to investigate the capability of Beta vulgaris (beetroot) water extract (BWE; 200 mg/kg) to protect hepatic tissue following silver nanoparticles (AgNPs; 80 mg/kg; >100 nm) intoxication in male rats. Results: AgNPs-intoxication elevated the liver function markers - including serum transaminases and alkaline phosphatase activities - and decreased serum levels of albumin and total proteins, in addition to disturbing the oxidation homeostasis. This is evidenced by the increased lipid peroxidation, the depleted glutathione, and the suppressed activity of superoxide dismutase and catalase. In addition, an apoptotic reaction was observed following AgNPs treatment, as indicated by the up-regulation of p53 and down-regulating Bcl-2 expressions, examined by the immunohistochemistry method. Furthermore, AgNPs exhibited a marked elevation in liver DNA damage that was indicated by an increase in tail length, tail DNA% and tail movement. However, BWE eliminated the biochemical and histological alterations, reflecting its hepatoprotection effect in response to AgNPs. Discussion: Collectively, the present data suggest that BWE could be used following AgNPs as a potential therapeutic intervention to minimize AgNPs-induced liver toxicity.


Assuntos
Beta vulgaris/química , Sucos de Frutas e Vegetais , Fígado/patologia , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Dano ao DNA , Fragmentação do DNA/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Testes de Função Hepática , Masculino , Nanopartículas Metálicas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53/metabolismo
18.
Aquat Toxicol ; 225: 105549, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32599437

RESUMO

Efficient antibacterial and antifungal properties of silver nanoparticles (AgNPs) sparked its commercial application in several industrial and household products. Drastic increase of AgNPs production raised concerns over aquatic organisms' exposure. The toxic dose, mechanism of toxicity, physiological damages, gene expression alteration, hematological and blood parameter distortion by AgNP needs to be investigated to explore inevitable risk in aquatic animals. In this study, rainbow trout (Oncorhynchus mykiss) (122.4 ± 1.4 g, 23.8 ± 0.7 cm) were exposed to colloidal AgNPs (28.3 ± 12.6 um) to determine the lethal concentration (LC50)(8.9 mg/l). Sub-lethal concentrations (10 %LC50, 25 %LC50, plus LC50 value) impact on hematologic, histological and molecular responses were evaluated. Results showed sever damage to blood cells morphology, and hematologic parameters change including RBC, WBC, Hct and Hb in all AgNP-treated groups. Histological damage in gill and liver of exposed fish were observed. Significant up-regulating of HSP70 and P53 genes were detected in response to AgNPs, whereas, it was found that in comparison to HSP70 gene, P53 induction occurred in lower AgNPs concentrations and lower exposure time. These results indicate adversely effects of AgNPs exposure to aquatic environments.


Assuntos
Nanopartículas Metálicas/toxicidade , Oncorhynchus mykiss/fisiologia , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brânquias/química , Oncorhynchus mykiss/metabolismo
19.
Chemosphere ; 258: 127348, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32540542

RESUMO

In this work, Fe2WO6 nanoparticles were synthesized by the ultrasound-assisted precipitation method. Various conditions were applied, including the change of the pH factor and reaction time for the synthesis of nanoparticles. After confirming the synthesis of the nanoparticles by various analyzes and evaluating their size and morphology, one of the conditions for the synthesis of the nanoparticles were selected as the optimum condition. The samples were added to the growth medium of a well-known microalga, Dunaliella salina at three concentrations of 20, 40 and 80 ppm to evaluate the effect of nanoparticles on biological systems. After 10 days different biological parameters were measured and compared with those of the control sample. According to the results, at concentration of 20 ppm the number of cells, the amount of chlorophyll a, and b, and biomass increased compared to the control samples. The Carotenoid level was higher in the treatment with 40 ppm of nanoparticles than that in the control samples. Compared to the control sample, the level of lipid peroxidation and the ratio of carbohydrate to amide II showed to be higher under 80 ppm treatment of particles. According to HCA analysis, both the evaluated parameters and concentrations of nanoparticles were divided into two general categories. Overall results showed that the effect of Fe2WO6 nanoparticles on microalgae could be a dose-dependent phenomenon, so that the addition of 20 ppm nanoparticles in the culture media helped the growth and the physiological status of algae. On the other hand, the application of a higher concentration of nanoparticles negatively affects algal biology. The results showed that the algae could be successfully used to precise screen of various nanoparticles in terms of safety especially in aquatic environments and also biotechnological applications.


Assuntos
Nanopartículas Metálicas/toxicidade , Microalgas/efeitos dos fármacos , Biomassa , Biotecnologia , Carotenoides/metabolismo , Clorofila A , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas
20.
Chemosphere ; 258: 127349, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32540544

RESUMO

The current understanding of the biological impacts of silver nanoparticles (AgNPs) is restricted to the direct interactions of the particles with biota. Very little is known about their intracellular fate and subsequent toxic consequences. In this research we investigated the uptake, internal fate (i,e., Ag subcellular partitioning and chemical forms), and phytotoxicity of AgNPs in lettuce following foliar versus root exposure. At the same AgNP exposure concentrations, root exposure led to more deleterious effects than foliar exposure as evidenced by a larger extent of reduced plant biomass, elevated oxidative damage, as well as a higher amount of ultrastructural injuries, despite foliar exposure leading to 2.6-7.6 times more Ag bioaccumulation. Both Ag subcellular partitioning and chemical forms present within the plant appeared to elucidate this difference in toxicity. Following foliar exposure, high Ag in biologically detoxified metals pool (29.2-53.0% by foliar exposure vs. 12.8-45.4% by root exposure) and low Ag proportion in inorganic form (6.1-11.9% vs. 14.1-19.8%) potentially associated with AgNPs tolerance. Silver-containing NPs (24.8-38.6 nm, 1.5-2.3 times larger than the initial size) were detected in lettuce plants exposed to NPs and to dissolved Ag+, suggesting possible transformation and/or aggregation of AgNPs in the plants. Our observations show that the exposure pathway significantly affects the uptake and internal fate of AgNPs, and thus the associated phytotoxicity. The results are an important contribution to improve risk assessment of NPs, and will be critical to ensure food security.


Assuntos
Alface/fisiologia , Nanopartículas Metálicas/toxicidade , Poluentes do Solo/toxicidade , Biomassa , Alface/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/química , Poluentes do Solo/química
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