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1.
Biosens Bioelectron ; 203: 114015, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35091378

RESUMO

A three-dimensional (3D) cell-based electrochemical sensor was developed to evaluate the immunomodulatory effects of atrazine and its metabolites by monitoring nitric oxide (NO) release. Nafion/Fe(III) meso-tetra (4-carboxyphenyl) porphyrin/reduced graphene oxide (Nafion/FeTCP@RGO) was functionalized on the screen-printed carbon electrode (SPCE) as a working electrode to enhance the NO selectivity and sensitivity. RAW264.7 cells encapsulated in a gelatin methacrylate (GelMA) hydrogel, forming a 3D cell culture system, were immobilized on the Nafion/FeTCP@RGO/SPCE to serve as biorecognition elements. The proposed sensor presented the induced NO expression as a distinct single differential pulse voltammetric (DPV) anodic peak in the selected physiological lipopolysaccharide (LPS) concentration range (0.01-2000 ng/mL). Furthermore, the peak current intensity of the NO was linearly correlated with the LPS concentration logarithm, which was further validated using a Griess reagent kit. The proposed sensor was utilized in optimized LPS-induction conditions to compare the immunosuppression effect of atrazine with its main metabolites (i.e. desethylatrazine (DEA), deisopropylatrazine (DIA), and diaminochlorotriazine (DACT)). The results demonstrated that the order of 30% inhibitory concentrations was atrazine (25.71 ± 1.08 µg/mL) < DEA (48.63 ± 2.17 µg/mL) ≤ DACT (49.11 ± 1.98 µg/mL) ≤ DIA (52.36 ± 2.34 µg/mL). Overall, this work provided a potential in vitro approach to evaluate the immunotoxicity of pesticides and their metabolites.


Assuntos
Atrazina , Técnicas Biossensoriais , Praguicidas , Atrazina/farmacologia , Eletrodos , Compostos Férricos
2.
Cell Physiol Biochem ; 55(6): 704-725, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34791862

RESUMO

BACKGROUND/AIMS: Pulmonary fibrosis can be caused by genetic abnormalities, autoimmune disorders or exposure to environmental pollutants. All these causes have in common the excessive production of oxidative stress species that initiate a cascade of molecular mechanism underlying fibrosis in a variety of organs, including lungs. The chemical name of Atrazine (ATR) is 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, and it is the most commonly used broad-spectrum herbicide in agricultural crops. Additionally, Bleomycin is a chemotherapeutic agent often used for different lymphoma with a seriously pulmonary complication. The most accredited hypothesis that may explain the mechanism of toxicity induced by ATR or bleomycin is exactly the production of reactive oxygen species (ROS) that leads to an unbalance in the physiological anti-oxidant system. However, until today, nobody has investigated the effect of ATR exposure during pulmonary fibrosis. METHODS: Mice were subject to ATR exposure, to bleomycin injection or to both. At the end of experiment, the lungs and blood were collected. Additionally, we analyzed by different test such as open field, pole and rotarod test or other we investigated the effects of ATR or bleomycin exposure on behavior. RESULTS: Following ATR or bleomycin induction, we found a significant increase in lung damage, fibrosis, and oxidative stress. This condition was significantly worsened when the animals injected with bleomycin were also exposed to ATR. Additionally, we observed significant motor and non-motor impairment in animals exposed to ATR. CONCLUSION: Our study demonstrates that ATR exposure, decrease nuclear factor-erythroid 2-related factor (Nrf2) pathways in both lung and brain.


Assuntos
Atrazina/efeitos adversos , Encefalopatias/metabolismo , Encéfalo/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Administração por Inalação , Animais , Atrazina/farmacologia , Bleomicina/efeitos adversos , Bleomicina/farmacologia , Encéfalo/patologia , Encefalopatias/etiologia , Encefalopatias/patologia , Masculino , Camundongos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/complicações , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia
3.
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
4.
Front Endocrinol (Lausanne) ; 12: 697505, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335472

RESUMO

Atrazine is one of the most commonly used pre-emergence and early post-emergence herbicides in the world. We have shown previously that atrazine does not directly stimulate the pituitary or adrenal to trigger hormone release but acts centrally to activate a stress-like activation of the hypothalamic-pituitary-adrenal axis. In doing so, atrazine treatment has been shown to cause adrenal morphology changes characteristic of repeated stress. In this study, adrenals from atrazine treated and stressed animals were directly compared after 4 days of atrazine treatment or restraint stress. Both atrazine and stressed animals displayed reduced adrenocortical zona glomerulosa thickness and aldosterone synthase (CYP11B2) expression, indicative of repeated adrenal stimulation by adrenocorticotropic hormone. To determine if reduced CYP11B2 expression resulted in attenuated aldosterone synthesis, stressed and atrazine treated animals were challenged with angiotensin II (Ang II). As predicted, stressed animals produced less aldosterone compared to control animals when stimulated. However, atrazine treated animals had higher circulating aldosterone concentrations compared to both stressed and control groups. Ang II-induced aldosterone release was also potentiated in atrazine pretreated human adrenocortical carcinoma cells (H295R). Atrazine pretreated did not alter the expression of the rate limiting steroidogenic StAR protein or angiotensin II receptor 1. Atrazine treated animals also presented with higher basal blood pressure than vehicle treated control animals suggesting sustained elevations in circulating aldosterone levels. Our results demonstrate that treatment with the widely used herbicide, atrazine, directly increases stimulated production of aldosterone in adrenocortical cells independent of expression changes to rate limiting steroidogenic enzymes.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Aldosterona/metabolismo , Angiotensina II/farmacologia , Atrazina/farmacologia , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Aldosterona/biossíntese , Animais , Células Cultivadas , Sinergismo Farmacológico , Feminino , Herbicidas/farmacologia , Ratos , Ratos Sprague-Dawley , Restrição Física/psicologia , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia
5.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360708

RESUMO

BACKGROUND: exposure to environmental contaminants has been linked to an increased risk of neurological diseases and poor outcomes. Chemical name of Atrazine (ATR) is 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, and it is the most commonly used broad-spectrum herbicide in agricultural crops. Several studies have demonstrated that ATR has the potential to be harmful to the brain's neuronal circuits. Until today nobody has explored the effect of ATR inhalation on young and aged mice. METHODS: young and aged mice were subject to 25 mg of ATR in a vehicle made with saline and 10% of Dimethyl sulfoxide (DMSO) every day for 28 days. At the end of experiment different behavioral test were made and brain was collected. RESULTS: exposure to ATR induced the same response in terms of behavioral alterations and motor and memory impairment in mice but in aged group was more marked. Additionally, in both young and aged mice ATR inhalations induced oxidative stress with impairment in physiological antioxidant response, lipid peroxidation, nuclear factor kappa-light-chain-enhancer of activated B cells (nf-κb) pathways activation with consequences of pro-inflammatory cytokines release and apoptosis. However, the older group was shown to be more sensitive to ATR inhalation. CONCLUSIONS: our results showed that aged mice were more susceptible compared to young mice to air pollutants exposure, put in place a minor physiologically response was seen when exposed to it.


Assuntos
Envelhecimento/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Atrazina/efeitos adversos , Encéfalo/metabolismo , Administração por Inalação , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Atrazina/farmacologia , Encéfalo/patologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos
6.
BMC Microbiol ; 20(1): 266, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847512

RESUMO

BACKGROUND: Atrazine is one of the most widespread chlorinated herbicides, leaving large bulks in soils and groundwater. The biodegradation of atrazine by bacteria is well described, but many aspects of the fungal metabolism of this compound remain unclear. Thus, we investigated the toxicity and degradation of atrazine by 13 rainforest basidiomycete strains. RESULTS: In liquid medium, Pluteus cubensis SXS320, Gloelophyllum striatum MCA7, and Agaricales MCA17 removed 30, 37, and 38%, respectively, of initial 25 mg L- 1 of the herbicide within 20 days. Deficiency of nitrogen drove atrazine degradation by Pluteus cubensis SXS320; this strain removed 30% of atrazine within 20 days in a culture medium with 2.5 mM of N, raising three metabolites; in a medium with 25 mM of N, only 21% of initial atrazine were removed after 40 days, and two metabolites appeared in culture extracts. This is the first report of such different outcomes linked to nitrogen availability during the biodegradation of atrazine by basidiomycetes. The herbicide also induced synthesis and secretion of extracellular laccases by Datronia caperata MCA5, Pycnoporus sanguineus MCA16, and Polyporus tenuiculus MCA11. Laccase levels produced by of P. tenuiculus MCA11 were 13.3-fold superior in the contaminated medium than in control; the possible role of this enzyme on atrazine biodegradation was evaluated, considering the strong induction and the removal of 13.9% of the herbicide in vivo. Although 88% of initial laccase activity remained after 6 h, no evidence of in vitro degradation was observed, even though ABTS was present as mediator. CONCLUSIONS: This study revealed a high potential for atrazine biodegradation among tropical basidiomycete strains. Further investigations, focusing on less explored ligninolytic enzymes and cell-bound mechanisms, could enlighten key aspects of the atrazine fungal metabolism and the role of the nitrogen in the process.


Assuntos
Agaricales/efeitos dos fármacos , Agaricales/metabolismo , Atrazina/metabolismo , Lacase/metabolismo , Agaricales/crescimento & desenvolvimento , Agaricales/isolamento & purificação , Atrazina/farmacologia , Biodegradação Ambiental , Meios de Cultura , Poluentes Ambientais/metabolismo , Matriz Extracelular/enzimologia , Proteínas Fúngicas/metabolismo , Nitrogênio/metabolismo , Polyporaceae/efeitos dos fármacos , Polyporaceae/metabolismo , Floresta Úmida , Especificidade da Espécie
7.
Int J Biol Macromol ; 163: 817-823, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653377

RESUMO

Biomimetic design represents an emerging field for improving knowledge of natural molecules, as well as to project novel artificial tools with specific functions for biosensing. Effective strategies have been exploited to design artificial bioreceptors, taking inspiration from complex supramolecular assemblies. Among them, size-minimization strategy sounds promising to provide bioreceptors with tuned sensitivity, stability, and selectivity, through the ad hoc manipulation of chemical species at the molecular scale. Herein, a novel biomimetic peptide enabling herbicide binding was designed bioinspired to the D1 protein of the Photosystem II of the green alga Chlamydomonas reinhardtii. The D1 protein portion corresponding to the QB plastoquinone binding niche is capable of interacting with photosynthetic herbicides. A 50-mer peptide in the region of D1 protein from the residue 211 to 280 was designed in silico, and molecular dynamic simulations were performed alone and in complex with atrazine. An equilibrated structure was obtained with a stable pocked for atrazine binding by three H-bonds with SER222, ASN247, and HIS272 residues. Computational data were confirmed by fluorescence spectroscopy and circular dichroism on the peptide obtained by automated synthesis. Atrazine binding at nanomolar concentrations was followed by fluorescence spectroscopy, highlighting peptide suitability for optical sensing of herbicides at safety limits.


Assuntos
Atrazina/farmacologia , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/fisiologia , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Sequência de Aminoácidos , Biomimética/métodos , Simulação de Dinâmica Molecular , Peptídeos/química , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/química , Conformação Proteica , Espectrometria de Fluorescência , Termodinâmica
8.
FEBS Lett ; 594(19): 3122-3141, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32677084

RESUMO

Target of rapamycin (TOR) kinase is a sensor and a central integrator of internal and external metabolic cues. However, in algae and in higher plants, the components of TOR kinase signaling are yet to be characterized. Here, we establish an assay system to study TOR kinase activity in Chlamydomonas reinhardtii using the phosphorylation status of its putative downstream target, CrS6K. Using this assay, we probe the modulation of cellular TOR kinase activity under various physiological states such as photoautotrophy, heterotrophy, mixotrophy, and nitrogen (N) starvation. Importantly, we uncover that excess acetate in the medium leads to high cellular reactive oxygen species levels, triggering autophagy and a concomitant drop in TOR kinase activity in a dose-dependent manner, thus leading to a N-starvation-like cellular phenotype, even when nitrogen is present.


Assuntos
Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/metabolismo , Estresse Fisiológico , Serina-Treonina Quinases TOR/metabolismo , Acetatos/metabolismo , Atrazina/farmacologia , Atrazina/efeitos da radiação , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/efeitos da radiação , Processos Heterotróficos/efeitos dos fármacos , Processos Heterotróficos/efeitos da radiação , Luz , Modelos Biológicos , Mutagênese Insercional/genética , Processos Fototróficos/efeitos dos fármacos , Processos Fototróficos/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/efeitos da radiação
9.
Sci Rep ; 10(1): 11088, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632188

RESUMO

Long-standing evidence supports the importance of maintaining healthy populations of microbiota for the survival, homeostasis, and complete development of marine mollusks. However, the long-term ecological effects of agricultural runoff on these populations remains largely unknown. Atrazine (6-Chloro-n-ethyl-n'-(1-methylethyl)-triazine-2,4-diamine), a prevalent herbicide in the United States, is often used along tributaries of the Chesapeake Bay where oyster breeding programs are concentrated. To investigate any potential effects atrazine maybe having on mollusk-prokaryote interactions, we used 16S rRNA gene amplicons to evaluate how microbial compositions shift in response to exposure of environmentally relevant concentrations of atrazine previously found within the Chesapeake Bay. The dominant bacterial genera found within all groups included those belonging to Pseudoalteromonas, Burkholderia, Bacteroides, Lactobacillis, Acetobacter, Allobaculum, Ruminococcus, and Nocardia. Our results support previously published findings of a possible core microbial community in Crassostrea virginica. We also report a novel finding: oysters exposed to atrazine concentrations as low as 3 µg/L saw a significant loss of a key mutualistic microbial species and a subsequent colonization of a pathogenic bacteria Nocardia. We conclude that exposure to atrazine in the Chesapeake Bay may be contributing to a significant shift in the microbiomes of juvenile oysters that reduces fitness and impedes natural and artificial repopulation of the oyster species within the Bay.


Assuntos
Atrazina/farmacologia , Bactérias/crescimento & desenvolvimento , Crassostrea/efeitos dos fármacos , Herbicidas/farmacologia , Microbiota/efeitos dos fármacos , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Crassostrea/crescimento & desenvolvimento , Crassostrea/microbiologia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
10.
Sci Rep ; 10(1): 9967, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561827

RESUMO

Despite the important ecological and agricultural production value of fallow field vegetation in agricultural landscapes, it is often affected by herbicide drift and runoff from neighboring sprayed fields. However, little is known about the impact of herbicides on the non-target plant community of fallow fields. In this study, the plant community of fallow fields was investigated following annual sublethal exposure to atrazine or tribenuron-methyl by a 3-year (2014-2016) randomized block field study. The two herbicides both changed the species composition, reduced the number of plant species and the relative frequencies of some plants, and significantly reduced the Margalef species richness index and Shannon's diversity index of the plant community in the fallow field. The effects of the two herbicides on species number and community composition were not consistent. The effects of herbicide doses less than the recommended field application concentration (RFAC) on the plant community composition and community diversity of the fallow field were not lower than the effects of the RFAC of the herbicides. Indeed, doses less than the RFAC had an even greater impact on the community diversity than the RFAC of the herbicides. As the number of years of herbicide application increased, the effects of the herbicides on the plant community diversity did not increase compared to the effects of the blank control, and the herbicides did not change the functional composition of the plant communities in the fallow field. Our results suggest that the ecological risks of herbicides, even at low concentrations, on non-target wild plant communities in agricultural landscapes should not be neglected in the development of practical plant diversity conservation strategies.


Assuntos
Herbicidas/farmacologia , Plantas/efeitos dos fármacos , Agricultura , Sulfonatos de Arila/farmacologia , Atrazina/farmacologia , Biodiversidade , China
11.
Microbes Environ ; 35(2)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32269200

RESUMO

Atrazine is a triazine herbicide that is widely used to control broadleaf weeds. Its widespread use over the last 50 years has led to the potential contamination of soils, groundwater, rivers, and lakes. Its main route of complete degradation is via biological means, which is carried out by soil microbiota using a 6-step pathway. The aim of the present study was to investigate whether application of atrazine to soil changes the soil bacterial community. We used 16S rRNA gene sequencing and qPCR to elucidate the microbial community structure and assess the abundance of the atrazine degradation genes atzA, atzD, and trzN in a Brazilian soil. The results obtained showed that the relative abundance of atzA and trzN, encoding triazine-initiating metabolism in Gram-negative and -positive bacteria, respectively, increased in soil during the first weeks following the application of atrazine. In contrast, the abundance of atzD, encoding cyanuric acid amidohydrolase-the fourth step in the pathway-was not related to the atrazine treatment. Moreover, the overall soil bacterial community showed no significant changes after the application of atrazine. Despite this, we observed increases in the relative abundance of bacterial families in the 4th and 8th weeks following the atrazine treatment, which may have been related to higher copy numbers of atzA and trzN, in part due to the release of nitrogen from the herbicide. The present results revealed that while the application of atrazine may temporarily increase the quantities of the atzA and trzN genes in a Brazilian Red Latosol soil, it does not lead to significant and long-term changes in the bacterial community structure.


Assuntos
Atrazina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Herbicidas/farmacologia , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Biodegradação Ambiental , Brasil , Genes Bacterianos , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , RNA Ribossômico 16S/genética , Solo/química , Poluentes do Solo/farmacologia , Clima Tropical
12.
PLoS One ; 15(3): e0230664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32208460

RESUMO

Recent empirical evidence suggests that herbicides have damaging effects on non-target organisms in both natural and semi-natural ecosystems. The African mound building termite, Macrotermes bellicosus, is an important beneficial insect that functions as an ecosystem engineer due to its role in the breakdown of dead and decaying materials. Here, we examined the effects of 2,4-D amine salt (2,4-D) and atrazine based herbicides viz. Vestamine® and Ultrazine® on the survival and locomotion response of M. bellicosus. Worker termites were treated with a range of concentrations of Vestamine® (the recommended concentration: 6.25 ml per 500 ml of water, 0.25- and 0.5-fold below the recommended concentration and distilled water as control) and Ultrazine® (the recommended concentration: 3.75 ml per 500 ml of water, 0.25-, 0.5-, 2.0- and 4-fold of the recommended concentration and distilled water as control) for 24 hours for the mortality test, and allowed to run for 15 seconds for the locomotion trial. All concentrations of both Vestamine® and Ultrazine® were highly toxic to worker termites and mortality increased as the concentration and time after treatment increased. For both herbicides, concentrations far less than the recommended rates caused 100% mortality. The speed of termites was significantly influenced by both Vestamine® and Ultrazine® as termites exposed to all tested concentrations of the herbicides exhibited reduced running speed than the control. These findings suggest that beneficial insects, especially M. bellicosus may experience high mortality (up to 100%) and reduced mobility if they are sprayed upon or come in contact with plant materials that have been freshly sprayed with (less or more than) the recommended concentrations of Vestamine® and Ultrazine®. The findings of our study calls for the reassessment of the usage of 2,4-D and atrazine based herbicides in weed control in termite and other beneficial insect populated habitats.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Atrazina/farmacologia , Herbicidas/farmacologia , Isópteros/fisiologia , Locomoção/efeitos dos fármacos , Animais , Ecossistema , Isópteros/efeitos dos fármacos
13.
Anal Chem ; 92(9): 6213-6217, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32124608

RESUMO

Single cell lipid profiling is a powerful tool to connect membrane composition and its changes within individual cells to specific biochemical functions or stimuli, but current approaches are inadequate due to the complex nature of the cells and technical limitation in analysis. Herein we report a new method with plasmonic substrates capable of cell localization and enhanced lipid ionization through thin-gold-film MALDI-MS. We performed lipidomic profiling of algae single cells with a 120-well microarray and identified more than 50 lipids in C. reinhardtii without an extraction process. The substrate was used for probing toxicological effect of herbicide atrazine on the algae's lipidome, demonstrating molecular changes in glycerol lipid profiles. Fast location of cells with metal-enhanced fluorescence (MEF) and subsequent precise and direct ionization of the LDI process contribute to the enhanced performance, allowing for assessment of lipid changes concurrent with atrazine affected populations. This method that combines microarrays, MEF, and MALDI-MS presents an effective platform for lipidomic study of single cells and for environmental toxicity study with microorganisms.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Lipidômica/métodos , Lipídeos/análise , Atrazina/farmacologia , Chlamydomonas reinhardtii/efeitos dos fármacos , Ouro/química , Herbicidas/farmacologia , Lipídeos/química , Análise em Microsséries , Análise de Célula Única , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
J Plant Physiol ; 238: 1-11, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31121522

RESUMO

Treatment of Arabidopsis thaliana seedlings with the PSII-inhibiting herbicide atrazine results in xenobiotic and oxidative stress, developmental arrest, induction of senescence and cell death processes. In contrast, exogenous sucrose supply confers a high level of atrazine stress tolerance, in relation with genome-wide modifications of transcript levels and regulation of genes involved in detoxification, defense and repair. However, the regulation mechanisms related to exogenous sucrose, involved in this sucrose-induced tolerance, are largely unknown. Characterization of these mechanisms was carried out through a combination of transcriptomic, metabolic, functional and mutant analysis under different conditions of atrazine exposure. Exogenous sucrose was found to differentially regulate genes involved in polyamine synthesis. ARGININE DECARBOXYLASE ADC1 and ADC2 paralogues, which encode the rate-limiting enzyme (EC 4.1.1.19) of the first step of polyamine biosynthesis, were strongly upregulated by sucrose treatment in the presence of atrazine. Such regulation occurred concomitantly with significant changes of major polyamines (putrescine, spermidine, spermine). Physiological characterization of a mutant affected in ADC activity and exogenous treatments with sucrose, putrescine, spermidine and spermine further showed that modification of polyamine synthesis and of polyamine levels could play adaptive roles in response to atrazine stress, and that putrescine and spermine had antagonistic effects, especially in the presence of sucrose. This interplay between sucrose, putrescine and spermine is discussed in relation with survival and anti-death mechanisms in the context of chemical stress exposure.


Assuntos
Arabidopsis/efeitos dos fármacos , Atrazina/farmacologia , Herbicidas/farmacologia , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo , Sacarose/farmacologia , Arabidopsis/metabolismo , Morte Celular/efeitos dos fármacos , Resistência a Herbicidas , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Plântula/efeitos dos fármacos , Plântula/metabolismo , Transcriptoma/efeitos dos fármacos
15.
J Agric Food Chem ; 67(16): 4453-4462, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30933503

RESUMO

Atrazine is one of the most used herbicides and has been associated with persistent surface and groundwater contamination, and novel formulations derived from nanotechnology can be a potential solution. We used poly(ε-caprolactone) nanoencapsulation of atrazine (NC+ATZ) to develop a highly effective herbicidal formulation. Detailed structural study of interaction between the formulation and Brassica juncea plants was carried out with evaluation of the foliar uptake of nanoatrazine and structural alterations induced in the leaves. Following postemergent treatment, NC+ATZ adhered to the leaf and penetrated mesophyll tissue mainly through the hydathode regions. NC+ATZ was transported directly through the vascular tissue of the leaves and into the cells where it degraded the chloroplasts resulting in herbicidal activity. Nanocarrier systems, such as the one used in this study, have great potential for agricultural applications in terms of maintenance of herbicidal activity at low concentrations and a substantial increase in the herbicidal efficacy.


Assuntos
Atrazina/química , Herbicidas/química , Mostardeira/efeitos dos fármacos , Nanopartículas/química , Atrazina/metabolismo , Atrazina/farmacologia , Composição de Medicamentos , Herbicidas/metabolismo , Herbicidas/farmacologia , Mostardeira/metabolismo , Nanopartículas/metabolismo , Nanotecnologia , Tamanho da Partícula , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento
16.
Chemosphere ; 225: 247-258, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877919

RESUMO

The study reports the effects of an herbicide (atrazine) and a plasticizer (Bisphenol A, BPA) on the transcriptional modulation of a mismatch repair gene (mlh1) and its adverse consequences on female fertility using Drosophila as a model. Through a chemical screen, we show that exposure to atrazine or BPA significantly downregulates mlh1 and the exposed flies had reduced fertility with smaller ovaries having reduced number of mature oocytes and abnormal distribution of ovarian follicles with increased apoptosis in them. These females had increased double-strand breaks as well as reduced synaptonemal complex formation in their ovaries suggesting altered meiotic crossing over. The eggs of these females were defective in their maternal transcripts as well as proteins and consequently, after fertilization, these eggs exhibited abnormal embryonic development. Interestingly, these phenotypes parallel that of mlh1 mutants. Further, exposure of females having reduced Mlh1 levels (mlh1e00130/CyO) to atrazine or BPA caused severe defective phenotypes at a higher proportion than normal flies. Our findings reveal the critical role of mlh1 in atrazine and BPA mediated female reproductive toxicity, and opens up a possibility of toxicants affecting female fertility by modulating the MMR genes.


Assuntos
Atrazina/farmacologia , Compostos Benzidrílicos/farmacologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Fertilidade/efeitos dos fármacos , Proteína 1 Homóloga a MutL/genética , Oogênese/genética , Fenóis/farmacologia , Animais , Drosophila melanogaster/efeitos dos fármacos , Feminino , Fertilidade/genética , Herbicidas/farmacologia , Oogênese/efeitos dos fármacos
17.
PLoS One ; 14(2): e0211936, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30779749

RESUMO

Modern transformation and genome editing techniques have shown great success across a broad variety of organisms. However, no study of successfully applied genome editing has been reported in a dinoflagellate despite the first genetic transformation of Symbiodinium being published about 20 years ago. Using an array of different available transformation techniques, we attempted to transform Symbiodinium microadriaticum (CCMP2467), a dinoflagellate symbiont of reef-building corals, with the view to performing subsequent CRISPR-Cas9 mediated genome editing. Plasmid vectors designed for nuclear transformation containing the chloramphenicol resistance gene under the control of the CaMV p35S promoter as well as several putative endogenous promoters were used to test a variety of transformation techniques including biolistics, electroporation and agitation with silicon carbide whiskers. Chloroplast-targeted transformation was attempted using an engineered Symbiodinium chloroplast minicircle encoding a modified PsbA protein expected to confer atrazine resistance. We report that we have been unable to confer chloramphenicol or atrazine resistance on Symbiodinium microadriaticum strain CCMP2467.


Assuntos
Núcleo Celular/genética , Cloroplastos/genética , Dinoflagelados/genética , Transformação Genética , Animais , Antozoários/microbiologia , Atrazina/farmacologia , Núcleo Celular/metabolismo , Cloranfenicol/farmacologia , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Dinoflagelados/metabolismo , Resistência a Medicamentos/genética
18.
Reprod Fertil Dev ; 31(5): 920-931, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30636190

RESUMO

Atrazine (ATZ) is one of the most widely used herbicides worldwide and is a common contaminant in human drinking water. It disrupts metabolic pathways in plants, and has metabolic and reproductive effects in vertebrates, including humans. Few studies have investigated the effects of exposure to low doses of ATZ, especially during sexual development in males. In this study, we exposed C57BL/6J male mice from weaning for 8 weeks to drinking water containing 0.5mgkg-1 bodyweight (BW) day-1 ATZ, the 'no observed effect' level used by the Australian government, or a 10-fold higher dose (5mgkg-1 BW day-1). Mice treated with the low dose of ATZ showed increased total and cumulative weight gain. At 12 weeks of age, there was a significant increase in the percentage of dead spermatozoa in both ATZ-exposed groups, as well as decreased epididymal sperm motility in the low-dose ATZ group. Significant changes in testis and liver gene expression were also observed following ATZ exposure. These data demonstrate that a low dose of ATZ can perturb metabolic and reproductive characteristics in male mice. A chronic reduction in sperm quality and increased weight gain could have negative consequences on the reproductive capacity of males, and further studies should consider the effects of long-term ATZ exposure on male reproductive health.


Assuntos
Atrazina/farmacologia , Expressão Gênica/efeitos dos fármacos , Herbicidas/farmacologia , Fígado/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Ganho de Peso/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Acrossomo/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Maturidade Sexual/fisiologia , Motilidade Espermática/efeitos dos fármacos , Testosterona/sangue
19.
J Environ Sci Health B ; 54(4): 290-293, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30633634

RESUMO

The extensive use of pesticides represents a risk to human health and to the environment. This study aimed to investigate if the exposure to atrazine and diuron, two herbicides widely used in Brazil, could induce changes in the susceptibility profile to aztreonam, colistin and polymyxin B antimicrobials in isolates of P. aeruginosa obtained from soil samples by using the determination of minimum inhibitory concentration (MIC) test. Three isolates had an increase of MIC to aztreonam after exposure to both herbicides and one isolate did not show any MIC change. The MexAB-OprM efflux pump has already been upregulated in these isolates and the herbicides atrazine and diuron did not increase MexAB-OprM overexpression. Therefore, the decrease in aztreonam susceptibility was not directly related to this pump, suggesting that probably other mechanisms should be involved.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Herbicidas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Microbiologia do Solo , Atrazina/farmacologia , Aztreonam/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Brasil , Colistina/farmacologia , Diurona/farmacologia , Farmacorresistência Bacteriana/genética , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Polimixina B/farmacologia , Pseudomonas aeruginosa/isolamento & purificação
20.
Biol Reprod ; 100(1): 41-48, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010721

RESUMO

Atrazine, a commonly used herbicide, suppresses the luteinizing hormone (LH) surge in female rats, although the underlying mechanism remains unclear. Kisspeptin, encoded by the Kiss1 gene, is a hypothalamic peptide that controls gonadotropin-releasing hormone (GnRH) release from the GnRH neurons. Kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) are involved in regulating pre-ovulatory GnRH and LH surge. To clarify the effect of atrazine on the LH surge in female rats, we investigated its effects on hypothalamic GnRH and kisspeptin. Ovariectomized female rats in a high-dose estradiol supplementation model were orally administered vehicle or 100 mg/kg of atrazine once daily for 5 days. This attenuated the LH surge but did not affect baseline LH levels, with no difference in hypothalamic GnRH levels between the vehicle-treated and atrazine-treated animals. After the fifth treatment, subcutaneous administration of kisspeptin (at 0, 0.1, 1, and 10 nmol/kg) induced a dose-dependent LH release almost equivalent in the vehicle- and atrazine-treated animals, suggesting that GnRH neurons maintain normal responsiveness to kisspeptin. However, Kiss1 mRNA expression levels in the AVPV were significantly reduced in the atrazine-treated animals. Given the normal response of GnRH neurons to exogenously administered kisspeptin, the suppressive effect of atrazine may be explained by suppression of Kiss1 expression in the AVPV leading to the attenuation of kisspeptin release from kisspeptin neurons in the AVPV. Further studies are warranted to elucidate more precisely the mechanism of atrazine's involvement in the suppression of Kiss1 mRNA expression in the AVPV.


Assuntos
Atrazina/farmacologia , Hipotálamo Anterior/efeitos dos fármacos , Hipotálamo Anterior/metabolismo , Kisspeptinas/genética , Hormônio Luteinizante/sangue , Animais , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Estradiol/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Hormônio Luteinizante/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
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