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1.
Chemosphere ; 287(Pt 1): 132104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34523452

RESUMO

The extensive use and environmental persistence of atrazine has resulted in its ubiquitous occurrence in water resources. Some reports have described atrazine bioaccumulation and biodegradation pathways in terrestrial plants, but few have done so in aquatic macrophytes. Thus, in this study, we aimed to analyze morphological changes, uptake, translocation and bioaccumulation patterns in tissues of the aquatic macrophyte Typha latifolia (cattail) after long-term atrazine exposure and to determine the presence of atrazine biodegradation metabolites, desethylatrazine (DEA) and desisopropylatrazine (DIA), in tissues. Plants were hydroponically exposed to 20 µg/L atrazine (18 exposed and 18 non-exposed) for 7, 14, 21, 28, 35 and 42 days. Plants were separated into root, rhizome, stem, and lower, middle and upper leaf sections. Atrazine was analyzed by LC-MS/MS and DIA and DEA by LC-DAD. Plants showed reductions in weight (after 21 days) and transpiration (after 28 days), both symptoms of chronic phytotoxicity. The distribution of atrazine within tissues, expressed as concentration levels (µg/kg dry weight), was as follows: middle leaf (406.10 ± 71.77) = upper leaf (339.15 ± 47.60) = lower leaf (262.43 ± 7.66) = sprout (274.53 ± 58.1) > stem (38.63 ± 7.55) = root (36.00 ± 3.49) = rhizome (26.15 ± 3.96). In submerged tissues, DEA and DIA were detected at similar concentrations. In leaves, DIA was the main metabolite identified. Results indicated that atrazine was taken up from roots to shoots and induced phytotoxicity effects that reduced the translocation to shoots. Typha likely is able to biodegrade atrazine via different metabolic pathways.


Assuntos
Atrazina , Herbicidas , Typhaceae , Atrazina/análise , Atrazina/toxicidade , Bioacumulação , Biodegradação Ambiental , Cromatografia Líquida , Herbicidas/toxicidade , Espectrometria de Massas em Tandem
2.
Sci Total Environ ; 807(Pt 1): 150609, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34619212

RESUMO

Triazine herbicides are widely used in agricultural production, and large amounts of herbicide residue enter the ocean through surface runoff. In this study, the toxicities of the triazine herbicides atrazine, prometryn and terbutryn (separately and mixed) to Phaeodactylum tricornutum were investigated. The EC50 values of atrazine, prometryn and terbutryn were 28.38 µg L-1, 8.86 µg L-1, and 1.38 µg L-1, respectively. The EC50 of an equitoxic mixture of the three herbicides was 0.78 TU, indicating that they had synergistic effects. The equitoxic mixture accumulated in P. tricornutum, which damaged chloroplast and mitochondria structures and significantly decrease the biomass, levels of key cellular components (such as chlorophyll a (chl a), carbon (C) and nitrogen (N) content, fatty acid content) and the effective photochemical quantum yield of photosystem II (PSII, ∆Fv/Fm). The mixture also downregulated key genes in the light response (PsbD, PetF), dark response (PGK, PRK), tricarboxylic acid (TCA) cycle (CS, ID, OGD, and MS) and fatty acid synthesis (FABB, SCD, and PTD9). P. tricornutum partially alleviates the effects of the mixture on photosynthesis and fatty acid synthesis by upregulating PetD, PsaB, RbcL and FabI expression. The triazine herbicide mixture reduced the biomass and nutritional value of marine phytoplankton by inhibiting photosynthesis and energy metabolism.


Assuntos
Atrazina , Herbicidas , Atrazina/toxicidade , Clorofila A , Herbicidas/toxicidade , Valor Nutritivo , Fotossíntese , Prometrina , Triazinas/toxicidade
3.
J Agric Food Chem ; 70(1): 87-98, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34936355

RESUMO

Atrazine (ATZ) is an agricultural pesticide for controlling field weeds. ATZ accumulates in many crops, posing high risks to crop production and food safety. Characterizing one of the novel rice MT genes named Oryza sativa atrazine-responsive methyltransferase (OsARM) showed that the expression of OsARM was associated with DNA demethylation (hypomethylation) in its promoter region. The enhancement of OsARM expression was manifested by the attenuated symptoms of ATZ toxicity including better growth and lower ATZ accumulation in plants. The promoted capacity of detoxification was confirmed by transgenic rice overexpression OsARM lines and also functionally proved by CRISPR-Cas9 knockout mutants. The transgenic lines accumulate more ATZ metabolites in rice and lower concentrations in the growth environment, pointing out that ATZ metabolism or degradation can be intensified. The ATZ-induced DNA demethylation is an important hallmark representing the epigenetic mechanism, which is required for the extra OsARM expression to facilitate ATZ disappearance in rice and the environment.


Assuntos
Atrazina , Herbicidas , Oryza , Praguicidas , Atrazina/toxicidade , Epigênese Genética , Herbicidas/toxicidade , Metiltransferases/genética , Oryza/genética
4.
J Agric Food Chem ; 69(42): 12527-12540, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34657419

RESUMO

The rapid development of nanotechnology influences the developments within the agro-sector. An example is provided by the production of nanoenabled pesticides with the intention to optimize the efficiency of the pesticides. At the same time, it is important to collect information on the unintended and unwanted adverse effects of emerging nanopesticides on nontarget plants. Currently, this information is limited. In the present study, we compared the effects of a nanoformulation of atrazine (NPATZ) and the nonencapsulated atrazine formulation (ATZ) on physiological responses, defense mechanisms, and nutrient displacement in lettuce over time with the applied concentrations ranging from 0.3 to 3 mg atrazine per kg soil. Our results revealed that both NPATZ and ATZ induced significant decreases in plant biomass, chlorophyll content, and protein content. Additionally, exposure to NPATZ and ATZ caused oxidative stress to the lettuce plant and significantly elevated the activities of the tested ROS scavenger enzymes in plant tissues. These results indicate that NPATZ and ATZ cause distinct adverse impacts on lettuce plants. When comparing the adverse effects in plants after exposure to NPATZ and ATZ, no obvious differences in plant biomass and chlorophyll content were observed between NPATZ and ATZ treatments at the same exposure concentration regardless of exposure duration. An enhanced efficiency of the active ingredient of the nanopesticide as compared to the conventional formulation was observed after long-term exposure to the high concentration of NPATZ, as it induced higher impacts on plants in terms of the end points of the contents of protein, superoxide anion (O2̇-), and MDA, and the activities of stress-related enzymes as compared to the same concentration of ATZ. Furthermore, exposure to both NPATZ and ATZ disrupted the uptake of mineral nutrients in plants, and the differences in the displacement of nutrients between the NPATZ and ATZ treatments depended on the element type, plant organ, exposure concentration, and time. Overall, the application dose of a nanopesticide should balance their increased herbicidal efficiency with the long-term adverse effects in order to maximize the desired impact while minimizing adverse impacts; only then will we be able to understand the potential impact of nanopesticides on the environment.


Assuntos
Atrazina , Herbicidas , Atrazina/farmacologia , Atrazina/toxicidade , Mecanismos de Defesa , Herbicidas/farmacologia , Herbicidas/toxicidade , Alface , Nutrientes
5.
Ecotoxicol Environ Saf ; 227: 112886, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673406

RESUMO

Atrazine (ATR) is a widely used herbicide that can induce the degeneration of dopaminergic (DAergic) neurons in the substantia nigra, resulting in a Parkinson's disease-like syndrome. Despite the high risk of environmental exposure, few studies have investigated strategies for the prevention of ATR neurotoxicity. Our previous studies demonstrated that ATR can impair mitochondrial function, leading to metabolic failure. Cells maintain mitochondrial quality through selective autophagic elimination, termed mitophagy. Soybean isoflavones (SI) possess multiple beneficial bioactivities, including preservation of mitochondria function, so it was hypothesized that SI can protect neurons against ATR toxicity by promoting mitophagy. Pretreatment of SH-SY5Y neurons with SI prevented ATR-induced metabolic failure and cytotoxicity as assessed by intracellular ATP, Na+-K+-ATPase activity, mitochondrial membrane potential, and cell viability assays. The neuroprotective efficacy of SI was superior to the major individual components genistein, daidzein, and glycitein. Ultrastructural analyses revealed that ATR induced mitochondrial damage, while SI promoted the sequestration of damaged mitochondria into autophagic vesicles. Soybean isoflavones also induced mitophagy as evidenced by upregulated expression of BNIP3/NIX, BEX2, and LC3-II, while co-treatment with the mitophagy inhibitor Mdivi-1 blocked SI-mediated neuroprotection and prevented SI from reversing ATR-induced BEX2 downregulation. Furthermore, BEX2 knockdown inhibited SI-induced activation of the BNIP3/NIX pathway, mitophagy, and neuroprotection. These findings suggest that SI protects against ATR-induced mitochondrial dysfunction and neurotoxicity by activating the BEX2/BNIP3/NIX pathway.


Assuntos
Atrazina , Isoflavonas , Atrazina/toxicidade , Neurônios Dopaminérgicos , Isoflavonas/farmacologia , Proteínas de Membrana , Mitofagia , Soja
6.
Environ Toxicol Pharmacol ; 88: 103749, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34547448

RESUMO

We developed phospho-ERK1/2 ELISA for human and rainbow trout liver cells, employing HepG2 and RTL-W1 cell lines as models. The assay was applied to detect changes in ERK1/2 activity for nine chemicals, added over a wide concentration range and time points. Cell viability was measured to separate ERK1/2 regulation from cytotoxicity. Perfluorooctane sulfonate and carbendazim did not change ERK1/2 activity; influence on ERK1/2 due to cytotoxicity was indicated for tributyltin and cypermethrin. Mancozeb, benzo[a]pyrene, and bisphenol A stimulated ERK1/2 up to ∼2- (HepG2) and 1.5 (RTL-W1)-fold, though the kinetics differed between chemicals and cell lines. Bisphenol A and benzo[a]pyrene were the most potent concentration-wise, altering ERK1/2 activity in pM (HepG2) to nM (RTL-W1) range. While atrazine and ibuprofen increased ERK1/2 activity by ∼2-fold in HepG2, they did not initiate an appreciable response in RTL-W1. This assay proved to be a sensitive, medium- to high-throughput tool for detecting unrecognized ERK1/2-disrupting chemicals.


Assuntos
Fígado/citologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Animais , Atrazina/toxicidade , Compostos Benzidrílicos/toxicidade , Benzimidazóis/toxicidade , Benzo(a)pireno/toxicidade , Carbamatos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fluorcarbonetos/toxicidade , Humanos , Ibuprofeno/toxicidade , Maneb/toxicidade , Oncorhynchus mykiss , Fenóis/toxicidade , Fosforilação/efeitos dos fármacos , Piretrinas/toxicidade , Compostos de Trialquitina/toxicidade , Zineb/toxicidade
7.
J Vet Diagn Invest ; 33(6): 1163-1167, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34384305

RESUMO

Ten of 40 cows died within 48 h of gaining access to a barn in which various chemicals were stored. Some of the surviving cows exhibited drooling, muscle tremors, and agitation. Postmortem examinations of 2 cows were performed in the field, and revealed nonspecific, moderate-to-severe pulmonary congestion. Liver and rumen contents, each from a different cow, were analyzed using a qualitative, multi-residue GC-MS method validated for the detection of pesticides and other chemical analytes. Using this method, extracts from the liver and rumen content samples were compared to atrazine (neat standard) and matrix-matched, control samples fortified with atrazine. GC-MS analysis detected atrazine at 215 m/z (NIST match >97%) with a retention time of ~13 min in liver and rumen content samples from our case. Detection of atrazine in the samples from the cows in this herd, combined with the clinical history, indicate that atrazine toxicity was the likely cause of clinical signs and death observed in this herd.


Assuntos
Atrazina , Animais , Atrazina/toxicidade , Bovinos , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária
8.
J Environ Manage ; 297: 113220, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274768

RESUMO

The pollutants in soils with different physicochemical properties usually exhibit various phytotoxicity due to their diverse environmental behavior. However, it is not clear that some components of dissolved organic matter (DOM) in soil affect the bioavailability of pollutants. In this study, the different phytotoxicity of atrazine in two different soils, black soil (BS) and yellow brown earth (YBE), to soybeen seedlings was investigated, and the potential mechanism were further discussed by examining the adsorption properties of atrazine with BS and YBE as well as the fluorescent characteristic variation of these two kinds of DOM extracted from BS and YBE during binding with atrazine. The results suggest that atrazine showed different phytotoxicity to soybean seedlings grown in BS and YBE. Specifically, the EC50 of atrazine on plant height and root length of soybean seedling in BS were 23.44 mg kg-1 and 54.29 mg kg-1, while those in YBE were 12.79 mg kg-1 and 21.48 mg kg-1. The adsorption amounts of BS and YBE was 41.56 mg kg-1 and 32.95 mg kg-1. In addition, 3D-EEM showed that humic acid-like substances were the main components of DOM in the two soils. With the increase of atrazine concentration, the fluorescence of these two kind of DOM was gradually quenched, but DOM-BS had a faster quenching rate. FT-IR showed that DOM-BS contained more polysaccharides and richer lipophilic groups. Meanwhile, the results of PARAFAC found that DOM-BS was easier to combine with atrazine. The findings of this study are significant to reveal phytotoxicity of atrazine in BS and YBE. The above results are helpful to better understand the components of DOM in different soils and their different role in regulating the environmental behavior and phytotoxicity of organic pollutants.


Assuntos
Atrazina , Poluentes do Solo , Adsorção , Atrazina/toxicidade , Substâncias Húmicas/análise , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Soja , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Environ Pollut ; 288: 117702, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34246997

RESUMO

The intestine is the main organ for nutrient absorption in amphibians. It is sensitive to atrazine, which is a herbicide widely used in agricultural areas. At present, there is a lack of systematic research on the effect of atrazine on the amphibian intestine. In this study, we evaluated the effects of atrazine exposure (0, 50 µg/L, 100 µg/L, and 500 µg/L) for 20 days on intestinal histology, microbiota and short chain fatty acids in Pelophylax nigromaculatus tadpoles. Our research showed that 500 µg/L atrazine exposure significantly decreased the height of microvilli and epithelial cells, and altered the composition and diversity of intestinal microbiota in P. nigromaculatus tadpoles compared to the control. At the phylum level, the abundance of Bacteroidetes and Fusobacteria increased significantly, while that of Verrucomicrobia and Firmicutes decreased significantly in the 500 µg/L atrazine treatment group. At the genus level, Akkermansia and Lactococcus had significantly lower abundance in the 100 µg/L and 500 µg/L atrazine exposure group, while Cetobacterium was only detected in the 100 µg/L and 500 µg/L atrazine treated group. Also, function prediction of intestinal microbiota showed that atrazine treatment significantly changed the metabolism pathways of P. nigromaculatus tadpoles. In addition, 500 µg/L atrazine exposure changed the content of short chain fatty acids by significantly increasing the content of total SFCAs, butyric acid, and valeric acid, and decreasing the content of isovaleric acid in the intestine. Taken together, atrazine exposure could affect the intestinal histology and induce intestinal microbiota imbalance and metabolic disorder in amphibian tadpoles.


Assuntos
Atrazina , Microbiota , Animais , Atrazina/toxicidade , Ácidos Graxos Voláteis , Intestinos , Larva , Ranidae
10.
Chemosphere ; 283: 131227, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34147975

RESUMO

Atrazine is considered as a potential environmental endocrine disruptors and exhibits various toxic effects on animals. It has a great impact in the aquatic ecosystems, but there are few studies on its immunotoxicity in crustaceans. In the present study, the Procambarus clarkii were utilized to assess the immune toxicity after 0.5 mg/L and 5 mg/L atrazine exposure. A significant decrease in total hemocytes count (THC) was observed at 5 mg/L atrazine exposure throughout the experiment. The activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were significantly inhibited, but the content of reactive oxygen species (ROS) and malondialdehyde (MDA) were up-regulated, indicating the potential oxidative stress. The analysis of the integrated biomarker response (IBR) showed the induction of oxidative stress biomarkers and the inhibition of antioxidants. After 5 mg/L atrazine exposure for 144 h, the integrity of crayfish hepatopancreas was destroyed with disappeared connections between tubules and increased liver tubules vacuoles. The relative expression levels of different immune genes in hepatopancreas after atrazine exposure were measured. Most of these genes were suppressed and exhibited a certain dose-dependent effect. The results of crayfish white spot syndrome virus (WSSV) replication shown the amount of virus in muscle was significantly higher and exhibited a higher mortality rate at 5 mg/L group than other groups. The present study determined the impact of atrazine exposure on WSSV outbreaks, and also provide an important basis for further assessing the occurrence of pesticides on diseases of P. clarkii.


Assuntos
Atrazina , Herbicidas , Vírus da Síndrome da Mancha Branca 1 , Animais , Astacoidea , Atrazina/toxicidade , Proliferação de Células , Ecossistema , Herbicidas/toxicidade , Estresse Oxidativo
11.
Environ Pollut ; 287: 117635, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34182386

RESUMO

The presence of atrazine, a triazine herbicide, and its residues in agriculture soil poses a serious threat to human health and environment through accumulation in edible plant parts. Hence, the present study focused on atrazine induced stress amelioration of Andrographis paniculata, an important medicinal plant, by a plant growth promoting and atrazine degrading endophytic bacterium CIMAP-A7 inoculation. Atrazine has a non-significant effect at a lower dose while at a higher dose (lower: 25 and higher: 50 mg kg-1) 22 and 36% decrease in secondary metabolite content and plant dry weight of A. paniculata was recorded, respectively. Endophyte CIMAP-A7 inoculation significantly reduced atrazine soil content, by 78 and 51% at lower and a higher doses respectively, than their respective control treatments. Inoculation of CIMAP-A7 exhibited better plant growth in terms of increased total chlorophyll, carotenoid, protein, and metabolite content with reduced atrazine content under both atrazine contaminated and un-contaminated treatments. Atrazine induced oxidative stress in A. paniculata was also ameliorated by CIMAP-A7 by reducing stress enzymes, proline, and malondialdehyde accumulation under contaminated soil conditions than un-inoculated treatments. Furthermore, the presence of atrazine metabolites deisopropylatrazine (DIA) and desethylatrazine (DEA) strongly suggests a role of CIMAP-A7 in mineralization however, the absence of these metabolites in uninoculated soil and all plant samples were recorded. These findings advocate that the amelioration of atrazine induced stress with no/least pesticide content in plant tissues by plant-endophyte co-interactions would be efficient in the remediation of atrazine contaminated soils and ensure safe crop produce.


Assuntos
Andrographis , Atrazina , Herbicidas , Poluentes do Solo , Atrazina/análise , Atrazina/toxicidade , Biodegradação Ambiental , Herbicidas/toxicidade , Humanos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
J Hazard Mater ; 418: 126350, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130159

RESUMO

Nanoparticles loaded with atrazine show weed control efficacy even with lower application doses of the active ingredient. Changes in the mode of action of the herbicide through the nanoformulation are key to understanding the efficiency of post-emergence activity of nanoatrazine. Here, we report the leaf absorption and translocation of nanoatrazine and atrazine employing radiometric techniques and compare their herbicidal effects in greenhouse and field conditions. Compared to the commercial formulation, nanoatrazine showed greater and faster absorption rates in mustard leaves (40% increment in the absorbed herbicide 24 h after application), inducing higher inhibition of photosystem II activity. Assays with fusicoccin-treated leaves indicated that the stomatal uptake of nanoparticles might be involved in the improved activity of nanoatrazine. Nanoencapsulation potentiated the post-emergent herbicidal activity of atrazine and the gain provided by nanoencapsulation was higher in the field compared to greenhouse conditions. Regardless of the dose, nanoatrazine provided two-fold higher weed control in the field compared to commercial atrazine. Thus, the design of this carrier system enables improvements in the performance of the herbicide in the field with less risk of environmental losses of the active ingredients due to faster absorption.


Assuntos
Atrazina , Herbicidas , Nanopartículas , Atrazina/toxicidade , Herbicidas/toxicidade , Polímeros , Controle de Plantas Daninhas
13.
Chemosphere ; 282: 130976, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34089999

RESUMO

Atrazine is one of the most widely used herbicides, however it and its metabolites cause widespread contamination in soil and ground water. Bioaugmentation is an effective method for remediation of environmental organic pollutants. High-throughput sequencing provides an important tool for understanding the changes of microbial community and function in response to pollutants degradation based on bioaugmentation. In this study, the effect of biodegradation with Paenarthrobacter sp. W11 and the change of microbial community during atrazine degradation were investigated. The results showed that bioaugmentation significantly accelerated the degradation rate of atrazine in soil and reduced the toxic effect of atrazine residues on wheat growth. The extra available NH4+ through atrazine mineralization could serve as a nitrogen source to increase microbial numbers. High-throughput sequencing further revealed that the microbial community restored a new balance. The function of microbial community predicted by PICRUSt2 suggested that the biodegradation process of atrazine affected not only the atrazine degradation pathway, but also the nitrogen metabolism pathway. Methylobacillus and Pseudomonas were considered as the most important indigenous atrazine-degrading microorganisms, because their relative abundances were positively correlated with the relative abundance of Paenarthrobacter and atrazine degradation pathway. This study provides insight into the cooperation between indigenous microorganisms and external inoculums on atrazine degradation process.


Assuntos
Atrazina , Herbicidas , Poluentes do Solo , Atrazina/análise , Atrazina/toxicidade , Biodegradação Ambiental , Herbicidas/análise , Herbicidas/toxicidade , Solo , Microbiologia do Solo , Poluentes do Solo/análise
14.
Ecotoxicol Environ Saf ; 220: 112386, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34090108

RESUMO

Atrazine (ATR) is a herbicide used widely worldwide. Because of its prolonged persistence in the environment and accumulation in the body, ATR exposure is a potential threat to human health. Our previous study showed that subacute exposure to ATR suppresses cellular immune function in mice. In this study, the effects of long-term exposure to ATR on rat immunological system function were measured. Four-week-old female Sprague-Dawley (SD) rats were treated with 0.4 µmol/L, 2 µmol/L and 10 µmol/L ATR for 24 weeks. The results showed that the spleen index increased, white blood cells decreased, and monocytes and eosinophils increased. No obvious changes were detected in the numbers of neutrophils and lymphocytes. Th1, Th2, and Th17 cells decreased significantly, while Treg cells increased after long-term ATR exposure. Moreover, serum levels of cytokines, including TNF-α, INF-γ, IL-6, and IL-12, decreased, while IL-1, IL-4, and IL-5 increased. Degenerative changes and cell apoptosis were found in the spleen; Caspase-3 and Caspase-9 were upregulated, and Bcl-2 was downregulated. These results suggested that long-term ATR exposure may inhibit immune system function.


Assuntos
Apoptose/efeitos dos fármacos , Atrazina/toxicidade , Herbicidas/toxicidade , Baço/efeitos dos fármacos , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Linfócitos T Auxiliares-Indutores
15.
Food Funct ; 12(11): 4855-4863, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33960999

RESUMO

Atrazine (ATR), a ubiquitous environmental contaminant in water and soil, causes environmental nephrosis. To reveal the toxic effect of ATR on the kidney and the potential chemical nephroprotective effect of lycopene (LYC), Kun-Ming mice of specific pathogen-free (SPF) grade were treated with LYC (5 mg kg-1) and/or ATR (50 mg kg-1 or 200 mg kg-1) for 21 days. The degree of renal injury was evaluated by measuring the ion concentration, ATPase activities and the mRNA expressions/levels of associated ATPase subunits. In addition, the expression of renal aquaporins (AQPs) was analyzed. The results showed that the renal tubular epithelial cells of ATR-exposed mice were swollen, the glomeruli were significantly atrophied, and the ion concentrations were obviously changed. The activity of Na+-K+-ATPase and the transcription of its subunits were downregulated. The activity of Ca2+-Mg2+-ATPase and the transcription of its subunits were upregulated. The expression of AQPs, especially the critical AQP2, was affected. Notably, ATR-induced nephrotoxicity was significantly improved by LYC supplementation. Therefore, LYC could protect the kidney against ATR-induced nephrotoxicity via maintaining ionic homeostasis, reversing the changes in ATPase activity and controlling the expression of AQPs on the cell membrane. These results suggested that AQP2 was a target of LYC and protected against ATR-induced renal ionic homeostasis disturbance.


Assuntos
Aquaporina 2/metabolismo , Atrazina/efeitos adversos , Homeostase , Rim/efeitos dos fármacos , Licopeno/farmacologia , Animais , Antioxidantes , Atrazina/toxicidade , Herbicidas/toxicidade , Rim/patologia , Masculino , Camundongos , ATPase Trocadora de Sódio-Potássio/metabolismo
16.
J Exp Zool A Ecol Integr Physiol ; 335(5): 512-521, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33949805

RESUMO

The widespread use of atrazine, a herbicide used to control weeds, has contributed to the increased contamination of aquatic environments. To assess the toxicological effects of a xenobiotic on a nontarget organism in the laboratory, different models of toxicological exposure systems have been widely used. Therefore, the aim of this study was to evaluate and compare the action of sublethal concentrations of atrazine on the hepatic histology of Oreochromis niloticus, considering two models of exposure: static (where atrazine was only added once) and semi-static (where atrazine was periodically renewed). Fish were exposed to a concentration of 2 ppm atrazine for 15 days, which was verified by high-performance liquid chromatography. The livers were stained with hematoxylin and eosin and histopathological data were collected. In addition, they were submitted to immunohistochemistry for inducible nitric oxide synthase (iNOS). A maximum variation of 45% (static) and 12.5% (semi-static) was observed between the observed and nominal atrazine concentration. Nuclear and cytoplasmic changes were observed in both experimental models. Hepatocytes from the livers of the static system showed a degenerative appearance, while in the semi-static system, intense cytoplasmic vacuolization and necrosis were observed. iNOS positive cells were identified only in macrophages in the hepatocytes of fish in the semi-static system. These results directly showed how the choice of exposure system can influence the results of toxicological tests. However, future analysis investigating the by-products and nitrogen products should be carried out since the histopathological findings revealed the possibility of these compounds serving as secondary contamination routes.


Assuntos
Atrazina/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Doenças dos Peixes/induzido quimicamente , Herbicidas/toxicidade , Animais , Atrazina/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ciclídeos , Esquema de Medicação , Herbicidas/administração & dosagem , Masculino , Poluentes Químicos da Água/toxicidade
17.
Chemosphere ; 274: 129845, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33979940

RESUMO

In this work, Caenorhabditis elegans was employed as an in vivo model to determine the toxic effects of atrazine at different concentrations. After the exposure period from the larval stage L1 to adulthood day 1, atrazine (10 mg/L) significantly decreased the body length and lifespan of nematodes. In addition, exposure to ≥0.01 mg/L atrazine remarkably increased the intestinal reactive oxygen species (ROS) levels and reduced locomotion behavior of nematodes, while exposure to ≥ 1 mg/L atrazine decreased the brood size of nematodes. Moreover, atrazine (0.001-0.1 mg/L) upregulated the expression levels of hsp-6::GFP and hsp-6/60 in nematodes, indicating the activation of mitochondrial unfolded protein response (mtUPR). On the contrary, atrazine (1-10 mg/L) downregulated the expression levels of hsp-6::GFP and hsp-6/60 in nematodes. Furthermore, mtUPR induction governed by the RNAi knockdown of atfs-1 could increase the vulnerability of nematodes against atrazine toxicity. Overall, our findings highlighted the dynamic responses of nematodes toward different concentrations of atrazine, which could be monitored using different sublethal endpoints as bioindicators.


Assuntos
Atrazina , Proteínas de Caenorhabditis elegans , Animais , Atrazina/toxicidade , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Locomoção , Estresse Oxidativo , Espécies Reativas de Oxigênio
18.
Sci Total Environ ; 780: 146666, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030342

RESUMO

Atrazine (ATR), a widely used herbicide that belongs to the triazine class, has detrimental effects on several organ systems. It has also been shown that ATR exposure results in dopaminergic neurotoxicity. However, the mechanism of herbicides causing ferroptosis in neurons is less concerned. So, the present study aimed to investigate the effects of long-term oral exposure to ATR on ferroptosis in adult male rats. In this study, we show that there was a dose-dependent increase in the concentration of iron in the midbrain. Simultaneously, the expression of tyrosine hydroxylase (TH) and Synuclein (α-syn) were altered by the ATR. We carried out miRNA profiling brain tissue in order to identify factors that mediate ferroptosis. We also found that the mRNA and protein expression of the transferrin receptor (TFR), divalent metal transporter 1 (DMT1), hephaestin (HEPH), and ferroportin 1 (Fpn1) in the midbrain were affected by ATR. Based on the current results and previously published data, it is clear that exposure of adult male rats to high doses of ATR leads to iron loading in the midbrain. The long-term adverse effects of ATR on the midbrain have a special relevance after exposure.


Assuntos
Atrazina , Herbicidas , Animais , Atrazina/toxicidade , Herbicidas/toxicidade , Ferro , Masculino , Mesencéfalo , Ratos , Ratos Sprague-Dawley
19.
Arch Environ Contam Toxicol ; 81(1): 123-132, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33891147

RESUMO

This paper presents a semiquantitative method to help ecotoxicologists evaluate the consistency of data within the available peer-reviewed literature. In this case study, we queried whether there is consistent evidence of direct toxicity in Anurans exposed to atrazine at concentrations ≤ 100 µg/L under laboratory conditions. Atrazine was selected because of the relatively large repository of Anuran toxicity data. To accomplish this, we interrogated available data found in recent quantitative weight-of-evidence risk assessments for atrazine with a series of yes or no questions developed a priori. The questions examined consistency of reported effects within and between studies, within and between species, and across a wide range of endpoints categories (e.g., survivorship, growth and development, reproduction). The analysis found no compelling evidence of a consistent direct effect in Anurans around growth and development, reproduction, or survivorship at concentrations of up to at least 100 µg/L atrazine in laboratory studies. Further work is needed to refine the approach, including accounting for the magnitude of the reported effects. However, we recommend that ecotoxicologists employ some method of formal consistency of effects assessment method routinely before performing toxicity tests, in the contextualizing of new data, and in reviews of contaminants.


Assuntos
Atrazina , Herbicidas , Poluentes Químicos da Água , Animais , Anuros , Atrazina/toxicidade , Herbicidas/toxicidade , Laboratórios , Poluentes Químicos da Água/toxicidade
20.
Sensors (Basel) ; 21(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804000

RESUMO

Plants naturally contain high levels of the stress-responsive fluorophore chlorophyll. Chlorophyll fluorescence imaging (CFI) is a powerful tool to measure photosynthetic efficiency in plants and provides the ability to detect damage from a range of biotic and abiotic stresses before visible symptoms occur. However, most CFI systems are complex, expensive systems that use pulse amplitude modulation (PAM) fluorometry. Here, we test a simple CFI system, that does not require PAM fluorometry, but instead simply images fluorescence emitted by plants. We used this technique to visualize stress induced by the photosystem II-inhibitory herbicide atrazine. After applying atrazine as a soil drench, CFI and color images were taken at 15-minute intervals, alongside measurements from a PAM fluorometer and a leaf reflectometer. Pixel intensity of the CFI images was negatively correlated with the quantum yield of photosystem II (ΦPSII) (p < 0.0001) and positively correlated with the measured reflectance in the spectral region of chlorophyll fluorescence emissions (p < 0.0001). A fluorescence-based stress index was developed using the reflectometer measurements based on wavelengths with the highest (741.2 nm) and lowest variability (548.9 nm) in response to atrazine damage. This index was correlated with ΦPSII (p < 0.0001). Low-cost CFI imaging can detect herbicide-induced stress (and likely other stressors) before there is visual damage.


Assuntos
Atrazina , Clorofila , Atrazina/toxicidade , Fluorescência , Imagem Óptica , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo
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