Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.327
Filtrar
1.
J Hazard Mater ; 416: 126203, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492966

RESUMO

Increasing electrical and electronic waste have raised concerns about the potential toxicity of brominated flame retardants (BFRs) and heavy metals (HMs). However, few studies have focused on the combined effect of BFRs and HMs on microorganisms, especially denitrifying bacteria, which have an essential role in N cycles and N2O emission. Herein, we investigate the combined effect of tetrabromobisphenol A (TBBPA) and Cu on model denitrifying bacteria. A further 24.5% decline in N removal efficiency was observed when 0.05 mg/L Cu were added into a denitrifying system containing 0.75 mg/L TBBPA. Further study demonstrated that Cu heightened the toxicity of TBBPA to denitrification via following aspects: (1) Cu stimulated EPS secretion induced by TBBPA during denitrification, blocked the transmembrane transport of glucose, which caused insufficient carbon substrate for bacteria growth and electron provision; (2) Cu further suppressed key denitrifying enzymes' activity and down-regulated genes involving electron transport induced by TBBPA, led to the decrease of electron transport activity. Finally, the decrease of bacterial growth, insufficient electron donor, and lower electron transport activity caused the synergetic toxic effect of TBBPA and Cu on denitrification. Overall, the present study provides new insights into the combined effect of BFRs and HMs on microorganisms.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Cobre/toxicidade , Desnitrificação , Transporte de Elétrons , Elétrons , Retardadores de Chama/toxicidade , Bifenil Polibromatos/toxicidade
2.
Chemosphere ; 282: 131051, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34470148

RESUMO

Marine tailing disposal (MTD) is sometimes practiced as an alternative to traditional mine tailing deposition on land. Environmental challenges connected to MTD include spreading of fine particulate matter in the water column and the potential release of metals and processing chemicals. This study investigated if tailing exposure affects the marine copepod Calanus finmarchicus, and whether effects are related to exposure to mineral particles or the presence of metals and/or processing chemicals in the tailings. We investigated the impacts of three different tailing compositions: calcium carbonate particles with and without processing chemicals and fine-grained tailings from a copper ore. Early life stages of C. finmarchicus were exposed over several developmental stages to low and high suspension concentrations for 15 days, and their development, oxygen consumption and biometry determined. The data was fitted in a dynamic energy budget (DEB) model to determine mechanisms underlying responses and to understand the primary modes of action related to mine tailing exposure. Results show that copepods exposed to tailings generally exhibited slower growth and accumulated less lipids. The presence of metals and processing chemicals did not influence these responses, suggesting that uptake of mineral particles was responsible for the observed effects. This was further supported by the applied DEB model, confirming that ingestion of tailing particles while feeding can result in less energy being available for growth and development.


Assuntos
Copépodes , Animais , Carbonato de Cálcio , Cobre/toxicidade , Metais , Material Particulado
3.
Mar Environ Res ; 170: 105447, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34438216

RESUMO

The toxicity of heavy metals to coastal organisms can be modulated by changes in pH due to progressive ocean acidification (OA). We investigated the combined impacts of copper and OA on different stages of the green macroalga Ulva linza, which is widely distributed in coastal waters, by growing the alga under the addition of Cu (control, 0.125 (medium, MCu), and 0.25 (high) µM, HCu) and elevated pCO2 of 1,000 µatm, predicted in the context of global change. The relative growth rates decreased significantly in both juvenile and adult thalli at HCu under OA conditions. The net photosynthetic and respiration rates, as well as the relative electron transfer rates for the adult thalli, also decreased under the combined impacts of HCu and OA, although no significant changes in the contents of photosynthetic pigments were detected. Our results suggest that Cu and OA act synergistically to reduce the growth and photosynthetic performance of U. linza, potentially prolonging its life cycle.


Assuntos
Ulva , Dióxido de Carbono , Cobre/toxicidade , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar
4.
Ecotoxicol Environ Saf ; 223: 112579, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352583

RESUMO

Limited data are available on metabolic responses of plants to copper (Cu)-toxicity. Firstly, we investigated Cu-toxic effects on metabolomics, the levels of free amino acids, NH4+-N, NO3--N, total nitrogen, total soluble proteins, total phenolics, lignin, reduced glutathione (GSH) and malondialdehyde, and the activities of nitrogen-assimilatory enzymes in 'Shatian' pummelo (Citrus grandis) leaves. Then, a conjoint analysis of metabolomics, physiology and transcriptomics was performed. Herein, 59 upregulated [30 primary metabolites (PMs) and 29 secondary metabolites (SMs)] and 52 downregulated (31 PMs and 21 SMs) metabolites were identified in Cu-toxic leaves. The toxicity of Cu to leaves was related to the Cu-induced accumulation of NH4+ and decrease of nitrogen assimilation. Metabolomics combined with physiology and transcriptomics revealed some adaptive responses of C. grandis leaves to Cu-toxicity, including (a) enhancing tryptophan metabolism and the levels of some amino acids and derivatives (tryptophan, phenylalanine, 5-hydroxy-l-tryptophan, 5-oxoproline and GSH); (b) increasing the accumulation of carbohydrates and alcohols and upregulating tricarboxylic acid cycle and the levels of some organic acids and derivatives (chlorogenic acid, quinic acid, d-tartaric acid and gallic acid o-hexoside); (c) reducing phospholipid (lysophosphatidylcholine and lysophosphatidylethanolamine) levels, increasing non-phosphate containing lipid [monoacylglycerol ester (acyl 18:2) isomer 1] levels, and inducing low-phosphate-responsive gene expression; and (d) triggering the biosynthesis of some chelators (total phenolics, lignin, l-trytamine, indole, eriodictyol C-hexoside, quercetin 5-O-malonylhexosyl-hexoside, N-caffeoyl agmatine, N'-p-coumaroyl agmatine, hydroxy-methoxycinnamate and protocatechuic acid o-glucoside) and vitamins and derivatives (nicotinic acid-hexoside, B1 and methyl nicotinate). Cu-induced upregulation of many antioxidants could not protect Cu-toxic leaves from oxidative damage. To conclude, our findings corroborated the hypothesis that extensive reprogramming of metabolites was carried out in Cu-toxic C. grandis leaves in order to cope with Cu-toxicity.


Assuntos
Citrus , Citrus/genética , Cobre/toxicidade , Metabolômica , Folhas de Planta , Plântula/genética , Transcriptoma
5.
J Environ Sci (China) ; 107: 150-159, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412778

RESUMO

The black soldier fly larvae (BSFL) have been successfully applied to treat various organic wastes. However, the impacts of heavy metals on antibiotic resistance in the BSFL guts are poorly understood. Here, we investigated the effect of copper (exposure concentrations of 0, 100 and 800 mg/kg) on the antibiotic and metal resistance profiles in BSFL guts. A total of 83 antibiotic resistance genes (ARGs), 18 mobile genetic elements (MGEs) and 6 metal resistance genes (MRGs) were observed in larval gut samples. Exposure to Cu remarkably reduced the diversity of ARGs and MGEs, but significantly enhanced the abundances of gut-associated ARGs and MRGs. The levels of MRGs copA, czcA and pbrT were dramatically strengthened after Cu exposure as compared with CK (increased by 2.8-13.5 times). Genera Enterococcus acted as the most predominant potential host of multiple ARG, MGE and MRG subtypes. Meanwhile, high exposure to Cu aggravated the enrichment of potential pathogens in BSFL guts, especially for Escherichia, Enterococcus and Salmonella species. The mantel test and procrustes analysis revealed that the gut microbial communities could be a key determinant for antibiotic and metal resistance. However, no significant positive links were observed between MGEs and ARGs or MRGs, possibly suggesting that MGEs did not play a crucial role in shaping the ARGs or MRGs in BSFL guts under the stress of Cu. These findings extend our understanding on the impact of heavy metals on the gut-associated antibiotic and metal resistome of BSFL.


Assuntos
Dípteros , Metais Pesados , Animais , Cobre/toxicidade , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Incidência , Larva , Metais Pesados/toxicidade
6.
Ecotoxicol Environ Saf ; 223: 112587, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352579

RESUMO

Cu is a metallic element that widely spread over in the environment, which have raised wide concerns about the potential toxic effects and public health threat. The objective of this study aimed to investigate the impression of copper (Cu)-triggered toxicity on mitochondrial dynamic, oxidative stress, and unfolded protein response (UPRmt) in fundic gland of pigs. Weaned pigs were randomly distributed into three groups, fed with different Cu of 10 mg/kg (control group), 125 mg/kg (group I), and 250 mg/kg (group Ⅱ). The trial persisted for 80 days and the fundic gland tissues were collected for further researches. Moreover, the markers participated to mitochondrial dynamic, UPRmt,and oxidative stress in fundic gland were determined. Results revealed that vacuolar degeneration were observed in the treated groups contrast with control group, and the Cu level was boosted with the increasing intake of Cu. Besides that, the levels of CAT, TRX, H2O2, and G6PDH were reduced in group Ⅰ and group Ⅱ, the mRNA levels of NRF2, HO-1, SOD-1, CAT, SOD-2, GSR, GPX1, GPX4, and TRX in the treated groups were promoted contrast to control group. Furthermore, the protein expression of KEAP1 was dramatically decreased, and the protein expression of NRF2, TRX and HO-1 were markedly enhanced in group Ⅰ and Ⅱ at 80 days. Moreover, the mRNA and protein expression levels of MFN1, MFN2, and OPA1 down-regulated and protein level of DRP1 was increased with the adding levels of Cu. Nevertheless, the UPRmt-related mRNA levels of CLPP, HTRA-2, CHOP, HSP10, and HSP60 were enhanced dramatically in Cu treatment group compared with control group. In general, our current study demonstrated that excessive absorption of Cu in fundic gland were related with stimulating UPRmt, oxidative stress, and the NRF2 interceded antioxidant defense. These results could afford an updated evidence on molecular theory of Cu-invited toxicity.


Assuntos
Cobre , Dinâmica Mitocondrial , Animais , Cobre/toxicidade , Peróxido de Hidrogênio , Proteína 1 Associada a ECH Semelhante a Kelch , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Suínos , Resposta a Proteínas não Dobradas
7.
Environ Pollut ; 287: 117645, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426373

RESUMO

Chronic toxicity of copper (Cu) at sublethal levels is associated with ionoregulatory disturbance and oxidative stress. These factors were considered in a toxicokinetic-toxicodynamic model in the present study. The ionoregulatory disturbance was evaluated by the activity of the Na+/K+-ATPase enzyme (NKA), while oxidative stress was presented by lipid peroxidation (LPO) and glutathione-S-transferase (GST) activity. NKA activity was related to the binding of Cu2+ and Na + to NKA. LPO and GST activity were linked with the simulated concentration of unbound Cu. The model was calibrated using previously reported data and empirical data generated when zebra mussels were exposed to Cu. The model clearly demonstrated that Cu might inhibit NKA activity by reducing the number of functional pump sites and the limited Cu-bound NKA turnover rate. An ordinary differential equation was used to describe the relationship between the simulated concentration of unbound Cu and LPO/GST activity. Although this method could not explain the fluctuations in these biomarkers during the experiment, the measurements were within the confidence interval of estimations. Model simulation consistently shows non-significant differences in LPO and GST activity at two exposure levels, similar to the empirical observation.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Cobre/análise , Cobre/toxicidade , Homeostase , Peroxidação de Lipídeos , Estresse Oxidativo , Toxicocinética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361024

RESUMO

The use of chemicals to boost food production increases as human consumption also increases. The insectidal, nematicidal and acaricidal chemical carbofuran (CAF), is among the highly toxic carbamate pesticide used today. Alongside, copper oxide nanoparticles (CuO) are also used as pesticides due to their broad-spectrum antimicrobial activity. The overuse of these pesticides may lead to leaching into the aquatic environments and could potentially cause adverse effects to aquatic animals. The aim of this study is to assess the effects of carbofuran and copper oxide nanoparticles into the cardiovascular system of zebrafish and unveil the mechanism behind them. We found that a combination of copper oxide nanoparticle and carbofuran increases cardiac edema in zebrafish larvae and disturbs cardiac rhythm of zebrafish. Furthermore, molecular docking data show that carbofuran inhibits acetylcholinesterase (AChE) activity in silico, thus leading to impair cardiac rhythms. Overall, our data suggest that copper oxide nanoparticle and carbofuran combinations work synergistically to enhance toxicity on the cardiovascular performance of zebrafish larvae.


Assuntos
Carbofurano/toxicidade , Inibidores da Colinesterase/toxicidade , Cobre/toxicidade , Coração/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Praguicidas/toxicidade , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Sítios de Ligação , Carbofurano/farmacologia , Cardiotoxicidade , Sinergismo Farmacológico , Praguicidas/farmacologia , Ligação Proteica , Peixe-Zebra
9.
Chemosphere ; 281: 130940, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289610

RESUMO

Copper-based nanoparticles (Cu-based NPs) have been gaining wide attention in agricultural applications due to their diverse characteristics and multipurpose properties. This includes their use in agrochemicals for efficient delivery and controlled release of pesticides and fertilizers. However, their excessive usage over a long duration of time could pose potential risks to the soil system. Further, they are known for their well-established anti-microbial effects which could be detrimental to soil health, particularly to the activities of soil microbes, which play a significant role in the functioning of terrestrial and agroecosystems. Thus, there is a great need to clearly understand these uniquely nanospecific properties of Cu-based NPs along with mode-of-action, effect on soil processes, soil organisms, and plants. This paper examines the current literature on Cu-based NPs to provide a systematic understanding of their potential impacts on the soil-plant environment. It explores their rising application and usage in agriculture along with their possible interaction with various soil components and the potential factors influencing it. It further investigates their uptake, translocation, and distribution in plants in various exposure media. It summarises that the dissolution, biotransformation, and bioavailability of Cu-based NPs in the soil are governed by several factors, like soil type, soil pH, and organic matter content. Further, environmental factors, time duration, and presence of other pollutants could also influence their biotransformation and soil toxicity. Finally, this review seeks to provide future perspectives that need attention for investigation purposes.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Poluentes do Solo , Cobre/toxicidade , Plantas , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
10.
Ecotoxicol Environ Saf ; 221: 112469, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198190

RESUMO

Glutathione S-transferase (GST) is the key enzyme in glutathione (GSH) synthesis, and plays a crucial role in copper (Cu) detoxification. Nonetheless, its regulatory mechanisms remain largely unclear. In this study, we identified a Cu-induced glutathione S-transferase 1 (TaGST1) gene in wheat. Yeast one-hybrid (Y1H) screened out TaWRKY74, which was one member from the WRKY transcription factor family. The bindings between TaGST1 promoter and TaWRKY74 were further verified by using another Y1H and luciferase assays. Expression of TaWRKY74 was induced more than 30-folds by Cu stress. Functions of TaWRKY74 were tested by using transiently silence methods. In transiently TaWRKY74-silenced wheat plants, TaWRKY74 and TaGST1 expression, GST activity, and GSH content was significantly inhibited by 25.68%, 19.88%, 27.66%, and 12.68% in shoots, and 53.81%, 52.11%, 23.47%, and 17.11% in roots, respectively. However, contents of hydrogen peroxide, malondialdehyde, or Cu were significantly increased by 2.58%, 12.45%, or 37.74% in shoots, and 25.24%, 53.84%, and 103.99% in roots, respectively. Notably, exogenous application of GSH reversed the adverse effects of transiently TaWRKY74-silenced wheat plants during Cu stress. Taken together, our results suggesting that TaWRKY74 regulated TaGST1 expression and affected GSH accumulation under Cu stress, and could be useful to ameliorate Cu toxicity for crop food safety.


Assuntos
Cobre/toxicidade , Glutationa Transferase/metabolismo , Glutationa/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Triticum/efeitos dos fármacos , Fatores de Transcrição/genética , Triticum/genética , Triticum/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Leveduras/genética
11.
Plant Physiol Biochem ; 166: 887-901, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34243016

RESUMO

Copper (Cu) is an essential micronutrient for plants, but when present in excess, it induces toxicity. In this study, cuttings of four wine-producing varieties of Vitis vinifera L. were used: 'Tinta Barroca', 'Tinto Cão', 'Malvasia Fina' and 'Viosinho'. The grapevine cuttings were distributed by hydroponic solutions enriched with different Cu concentrations (1, 10, 25 and 50 µM) plus control. At the end of the experiment, the root growth was evaluated, and individual roots were collected, fixed, and used for histological sections and chromosome spreads preparation. The higher Cu concentrations induced toxicity and inhibited root growth. However, the grapevine varieties responded with the thickening of the root exodermis and endodermis. In the chromosome spreads, normal and abnormal interphase and mitotic cells were observed in all varieties and treatments. The increase of Cu concentration decreased the nucleolar activity, as seen by reducing the nucleolar number and area. It increased the frequency of interphase cells with anomalies (ICA), but it did not influence total soluble protein concentration. The augment of Cu concentration also decreased the mitotic index (MI) and increased the percentage of dividing cells with anomalies (DCA). Different types of chromosomal anomalies in all mitotic phases, treatments and varieties were found. Overall, the white wine varieties, 'Malvasia Fina' and 'Viosinho', appeared to be more tolerant to the Cu-induced stress because they showed higher root growth and mean MI and lower mean DCA than the red wine varieties.


Assuntos
Vitis , Vinho , Cobre/toxicidade , Hidroponia , Índice Mitótico , Raízes de Plantas
12.
Environ Sci Technol ; 55(15): 10769-10783, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34308629

RESUMO

A thorough understanding of the implications of chronic low-dose exposure to engineered nanomaterials through the food chain is lacking. The present study aimed to characterize such a response in Cucurbita pepo L. (zucchini) upon exposure to a potential nanoscale fertilizer: copper oxide (CuO) nanoparticles. Zucchini was grown in soil amended with nano-CuO, bulk CuO (100 mg Kg-1), and CuSO4 (320 mg Kg-1) from germination to flowering (60 days). Nano-CuO treatment had no impact on plant morphology or growth nor pollen formation and viability. The uptake of Cu was comparable in the plant tissues under all treatments. RNA-seq analyses on vegetative and reproductive tissues highlighted common and nanoscale-specific components of the response. Mitochondrial and chloroplast functions were uniquely modulated in response to nanomaterial exposure as compared with conventional bulk and salt forms. X-ray absorption spectroscopy showed that the Cu local structure changed upon nano-CuO internalization, suggesting potential nanoparticle biotransformation within the plant tissues. These findings demonstrate the potential positive physiological, cellular, and molecular response related to nano-CuO application as a plant fertilizer, highlighting the differential mechanisms involved in the exposure to Cu in nanoscale, bulk, or salt forms. Nano-CuO uniquely stimulates plant response in a way that can minimize agrochemical inputs to the environment and therefore could be an important strategy in nanoenabled agriculture.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Nanoestruturas , Cobre/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos , Raízes de Plantas , Solo
13.
Sci Total Environ ; 796: 148974, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34271378

RESUMO

Nanosized agrochemicals like nanofertilizers are being applied to soils. Adverse impacts of nanofertilizers on soil microflora were reported in past studies, but only considering a single application. Repeated applications are however more likely to occur in agriculture. We investigated effects of single versus repeated applications of a copper hydroxide nanofertilizer formulation (NFF) on soil enzyme activity and bacterial community. One or three applications were performed within 21 days to achieve same final level of Cu in soil (48 mg(Cu)/kg: the recommended dose of NFF). Besides, the active ingredient (i.e., copper hydroxide nanotubes (NT)) and dispersing agent (DA) of NFF, and an ionic fertilizer (i.e., CuSO4) were examined. Fluorescein diacetate hydrolase (FDAse), N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP), and urease (URE) showed negligible changes in the activities between the control and DA treatment. Bacterial community abundance, composition and diversity exhibited similar phenomena. Exposures to copper hydroxide NFF and NT or CuSO4 enhanced the activities of FDAse and NAG, weakened the activity of URE, and showed negligible changes in the LAP activity irrespective of single and repeated applications. Concentrations of NO3--N and NH4+-N in soil were also affected by the application mode of NFF. More importantly, responses of soil bacterial community to copper hydroxide NFF were highly dependent on its application mode, whereas similar responses were observed in the CuSO4 treatment regardless of single or repeated applications. This study provided new insights into environmental risk of copper hydroxide NFF that were ignored in previous studies using a single exposure.


Assuntos
Poluentes do Solo , Solo , Cobre/análise , Cobre/toxicidade , Hidróxidos , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
14.
Ecotoxicol Environ Saf ; 222: 112494, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265532

RESUMO

Copper (Cu) pollution in water and agricultural soil has always been a worldwide concern. This research aims to investigate the health effects of copper exposure on Caenorhabditis elegans (C. elegans) under the existing environmental quality standards (1 mg/L and 2 mg/L) via lifespan, reproduction, biological markers and transcriptome analysis. The results showed that copper of these two environmental standards shorten the lifespan of nematodes, reduced the brood size, reduced the frequency of pharyngeal pumps and prolonged defecation time as aging-related behaviors, and increased the levels of aging-related markers ROS, MDA and H2O2. There was a certain effect trend for the two exposure concentrations. Further, the possible molecular mechanism of copper-induced aging and reproductive effects on C. elegans was explored. Differential gene expression analysis was performed, and 2332 genes (567 up- and 1765 down-regulated genes) in the 1 mg/L group, 2449 DEGs (724 up- and 1725 down-regulated genes) in the 2 mg/L group in response to copper treatment. The top 20 regulated genes were vit (vit-1, vit-3, vit-4) genes, col genes (col-35, col-72, col-114, col-123, col-164, col-183, col-185), eea-1, him-18 and grl-20, which suggested that cuticle collagen synthesis and yolk expression were disrupted by copper. Analysis of KEGG pathway showed copper exposure widely affects longevity regulation pathways, thereby promoting aging. In summary, the sequencing results extensively and deeply reveal the health hazards of environmentally relevant doses of copper exposure to C. elegans, and behavioral testing verified that copper promoted aging of C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Escala de Avaliação Comportamental , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Cobre/toxicidade , Peróxido de Hidrogênio , Longevidade , Masculino , Transcriptoma
15.
Ecotoxicol Environ Saf ; 222: 112518, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271501

RESUMO

Copper (Cu), as a common chemical contaminant in environment, is known to be toxic at high concentrations. The current research demonstrates the effects of copper upon hepatocyte cell-cycle progression (CCP) in mice. Institute of cancer research (ICR) mice (n = 240) at an age of four weeks were divided randomly into groups treated with different doses of Cu (0, 4, 8, and 16 mg/kg) for 21 and 42 days. Results showed that high Cu exposure caused hepatocellular G0/G1 cell-cycle arrest (CCA) and reduced cell proportion in the G2/M phase. G0/G1 CCA occurred with down-regulation (p < 0.05) of Ras, p-PI3K (Tyr458), p-Akt (Thr308), p-forkhead box O3 (FOXO3A) (Ser253), p-glycogen synthase kinase 3-ß (GSK3-ß) (Ser9), murine double minute 2 (MDM2) protein, and mRNA expression levels, and up-regulation (p < 0.05) of PTEN, p-p53 (Ser15), p27, p21 protein, and mRNA expression levels, which subsequently suppressed (p < 0.05) the protein and mRNA expression levels of CDK2/4 and cyclin E/D. These results indicate that Cu exposure suppresses the Ras/PI3K/Akt signaling pathway to reduce the level of CDK2/4 and cyclin E/D, which are essential for the G1-S transition, and finally causes hepatocytes G0/G1 CCA.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Linhagem Celular Tumoral , Proliferação de Células , Cobre/toxicidade , Pontos de Checagem da Fase G1 do Ciclo Celular , Quinase 3 da Glicogênio Sintase , Camundongos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
16.
Ecotoxicol Environ Saf ; 222: 112520, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280842

RESUMO

Mineral development and metal smelting are the main sources of heavy metal pollution, and copper (Cu) and cadmium (Cd) are the most serious mineral elements in heavy metal pollution. Food chain is the main channel for Cu and Cd to enter human body. Excessive accumulation of Cu and Cd can lead to a variety of diseases and threaten human health. Therefore, it is urgent to repair Cu and Cd-contaminated soil. Previous several studies found that sulfur (S) and molybdenum (Mo) had the effect of alleviating the decrease of antioxidant capacity caused by heavy metal poisoning. To investigate the co-combinations of S and Mo fertilizations on antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-contaminated meadow, and explore the control methods of co-pollutions of Cu and Cd in natural pastures, fertilizing and grazing experiments were carried out in the Wumeng Prairie in the northwest of Guizhou Province, Southwest China. 24 hm2 Cu and Cd-polluted meadows were fenced, and were randomly divided into four groups with 3 replications per group and 2 hm2 per replication. The tested groups included the control group (no fertilizer) and the three treatment groups, applied 40 kg S + 1 kg Mo, 80 kg S + 2 kg Mo, and 120 kg S + 3 kg Mo per hectare for group I, group II, and group III, respectively. 72 healthy Guizhou semi-fine wool sheep (one year old, 33.9 ± 1.2 kg) were randomly assigned to the tested pastures with 18 sheep per group. The grazing experiment lasted for 60 days. The results showed that the contents of Mn, Zn, Mo, and S in herbage in fertilized pastures were higher than that in the control group (P < 0.05). The content of Cu in herbage in fertilized pastures was lower than that in the control group (P < 0.05). The contents of Mn, Zn, Mo, and S in serum of grazing Guizhou semi-fine wool sheep were higher than that in the control group (P < 0.05). The content of Cu in serum of grazing Guizhou semi-fine wool sheep was lower than that in the control group (P < 0.05). The levels of blood Hb, RBC, and PCV, and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp in group Ⅲ were higher than that in the control group, group Ⅰ, and group Ⅱ (P < 0.05). The MDA content of sheep in group Ⅲ was lower than that in the other treatment sheep (P < 0.05). In summary, the combinations of S and Mo fertilizers influenced the mineral contents in herbage and serum of grazing Guizhou semi-fine wool sheep. The combinations of 120 kg S + 3 kg Mo fertilizer reduced the toxicity and improved antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-polluted grasslands.


Assuntos
Cádmio , , Animais , Antioxidantes , Cádmio/toxicidade , Cobre/toxicidade , Fertilização , Humanos , Molibdênio/toxicidade , Ovinos , Enxofre
17.
Artigo em Inglês | MEDLINE | ID: mdl-34201491

RESUMO

In the present study, the effects of copper oxide nanoparticles (CuO NPs) on bioactive compounds, the ultrastructural modifications which can occur, and elemental content of wheat were investigated. Changes in the wheat plants grown in presence or absence of CuO NPs were estimated. The application of CuO NPs decreased the amounts of chlorophylls and carotenoids and increased the amounts of polyphenols and antioxidant capacity. Ultrastructural analysis showed that the plants treated with CuO NPs were negatively affected. Soil amending completely inhibited the accumulation of seventeen elements, while K, Br, Al, and Zn were accumulated and Cl, Na, Ba, and Sr content decreased in wheat samples, regardless of the type of NPs applied. The application of chemically obtained NPs induced the most significant changes, completely blocking the assimilation of Fe, Mo, As, Sb, and Sm, and favoring much higher accumulation of Br than biogenic NPs. The decrease in chlorophylls and carotenoids is correlated with increase in antioxidant capacity, and occurs with increase of Mo, Al, Mg, K, Zn, and Ca content. The behavior of total polyphenols is correlated with Br content, and antagonist to Al behavior. From the point of view of bioactive compounds, the most affected plants were those that grew in the presence of CuO-NP-cel, while from the point of view of elementary analysis, the most affected plants were those grown in the presence of CuO-NP. By corroborating the obtained results, it was found that the CuO NPs have a negative effect on wheat plants.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Cobre/toxicidade , Íons , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Solo , Triticum
18.
Ecotoxicol Environ Saf ; 223: 112547, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34330039

RESUMO

Excessive amounts of copper (Cu) in soils causes toxic effects on plants. In this study, 58 rice cultivars were classified into tolerant, moderately tolerant, and susceptible types for Cu(II) toxicity based on 50% germination (LC50). Nine japonica rice varieties (three each from the tolerant, moderately tolerant, and susceptible groups) and six indica rice varieties (three from the moderately tolerant and susceptible groups) were selected for the hydroponics experiments. In the short-term adsorption experiment, Cu(II) adsorbed on rice roots was differentiated into exchangeable, complexed, and precipitated forms. Similarly, it was done for long-term culture. Absorption of Cu(II) by rice roots and shoots was also measured. The results indicated that adsorbed Cu(II) mainly existed as complexed and exchangeable forms on rice roots in the short-term adsorption experiment, and the exchangeable and complexed Cu(II) levels were greater for indica rice than for japonica rice due to the larger negative charge on the indica rice roots. The adsorbed Cu(II) mainly existed as a complexed form in the long-term culture experiment, and the exchangeable Cu(II) level was much lower than that in the short-term adsorption experiment due to the absorption of Cu(II) by rice plants. The indica varieties absorbed more Cu(II) than the japonica varieties. Furthermore, the absorption and accumulation of Cu(II) by the susceptible varieties were greater than by the tolerant and moderately tolerant varieties for both the japonica and indica rice. The absorption and accumulation of Cu(II) in rice roots were much greater than in the shoots. Chlorophyll content, and the lengths and dry matter weights of the rice roots and shoots decreased with increasing Cu(II) concentration. The Cu(II) showed greater toxicity toward indica varieties than japonica varieties, and the greater negative charge on indica roots was one of reasons for the greater exchangeable Cu(II) on the roots, the increase in Cu(II) toxicity, and the higher uptake of Cu(II) by indica rice varieties compared to japonica rice varieties.


Assuntos
Oryza , Poluentes do Solo , Adsorção , Cobre/toxicidade , Solo , Poluentes do Solo/toxicidade
19.
Sci Total Environ ; 790: 148087, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34091329

RESUMO

The coexistence of antibiotics, heavy metals and microplastics is becoming commonplace and may affect antibiotic resistance in manured soil. The current understanding of the role of microplastics in soil with combined pollution of antibiotics, heavy metals and antibiotic resistance genes (ARGs) is limited. Here, the effects of the coexistence of tetracycline (TC), Cu and environmental microplastics (EM) on the fate of nine ARGs and three heavy metal resistance genes in agricultural soil were investigated by batch and microcosm experiments. EM were obtained by exposing virgin microplastics to soil environments for 80 days, which exhibited higher adsorption affinity for Cu and TC than soil particles and virgin microplastics. 1% EM in soil increased bioavailable concentrations of TC and Cu by 79-138% and 88-135%, respectively, and decreased TC dissipation from 11.79 mg kg-1 to 3.08 mg kg-1. Correspondingly, the total relative abundances of target ARGs increased by 219-348%. The significant correlations of tetG, tetB, tetQ, sul2, sul1 and intl1 with bioavailable fractions of TC and Cu in soil environments were revealed by network analysis. Moreover, scanning electron micrographs showed the special plastisphere around EM. Attributed to the biofilm generation and higher pollutant accumulation in the plastisphere, EM could be the source of antibiotic-resistant bacteria and ARGs in soil environments. Structure equation models further identified that indirect effects of EM acted a major role in the propagation of ARGs by altering soil properties, soil microbial diversity and intl1 abundance. This study revealed that EM could increase the stimulative effects of Cu and TC on antibiotic resistance and magnify the environmental risk of manure application in soil environments.


Assuntos
Esterco , Solo , Antibacterianos/farmacologia , Cobre/toxicidade , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Microplásticos , Plásticos , Microbiologia do Solo , Tetraciclina/toxicidade
20.
Environ Pollut ; 287: 117603, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34147778

RESUMO

Extreme temperatures from marine heatwaves (MHWs) and pollution are dominant stressors in tropical marine ecosystems. However, we know little about the role of transgenerational effects of metals and MHWs in shaping the offspring's vulnerability to these stressors. We addressed this fundamental knowledge gap by exposing the planktonic copepod Pseudodiaptomus incisus to copper (Cu: control, 15 and 60 µg L-1) under 2 temperatures (30 and a simulated marine heatwave at 34 °C) in the first generation (F1) and 16 treatments in F2: offspring from each of 4 F1 conditions (control or 15 µg Cu L-1 × 30 or 34 °C) was reared in 4 F2 conditions (control or 15 µg Cu L-1 × 30 or 34 °C). We assessed changes in copepod performance, particularly survival, adult size, grazing, and reproduction. In F1, Cu or marine heatwave (MHW) exposures reduced all fitness traits of F1; the effects were particularly strong when both stressors were present. Transgenerational effects of Cu or MHW also strongly reduced F2 performance. Direct Cu and MHW effects on the offspring were further strengthened by transgenerational effects, resulting in more substantial reductions in F2 performance when both generations were exposed to these stressors. As copepods are major food resources for corals, shrimps, or fish larvae and juveniles, strong transgenerational and direct effects of Cu and MHW can have a cascading effect on entire coastal food webs. These results highlight the importance of considering the interaction of transgenerational and direct effects of multiple stressors, particularly relevant for short-lived organisms in tropical marine ecosystems.


Assuntos
Copépodes , Animais , Cobre/toxicidade , Ecossistema , Cadeia Alimentar , Metais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...