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1.
Chemosphere ; 294: 133742, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35090847

RESUMO

Difenoconazole, a typical triazole fungicide, inhibits the activity of cytochrome P450 enzyme in fungi, and is extensively used in protecting fruits, vegetables, and cereal crops. However, reports elucidating the effects of difenoconazole on aquatic microbial communities are limited. Our study showed that difenoconazole promoted microalgae growth at concentrations ranging from 0.1 to 5 µg/L, which was similar with its environmental residual concentrations. Metagenomic analysis revealed that the aquatic microbial structure could self-regulate to cope with difenoconazole-induced stress by accumulating bacteria exhibiting pollutant degrading abilities. In the short-term, several functional pathways related to xenobiotic biodegradation and analysis were upregulated to provide ability for aquatic microbial community to process xenobiotic stress. Moreover, most disturbed ecological functions were recovered due to the redundancy of microbial communities after prolonged exposure. Furthermore, the risks associated with the dissemination of antibiotic resistance genes were enhanced by difenoconazole in the short-term. Overall, our study contributes to a comprehensive understanding of the difenoconazole-induced ecological impacts and the behavior of aquatic microbial communities that are coping with xenobiotic stress.


Assuntos
Dioxolanos , Fungicidas Industriais , Microbiota , Dioxolanos/toxicidade , Água Doce , Fungicidas Industriais/metabolismo , Triazóis/química
2.
Toxins (Basel) ; 13(12)2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34941692

RESUMO

Difenoconazole (DIF) and dimethomorph (DIM) are widely used pesticides frequently detected together in environmental samples, so the deleterious effects of combined exposure warrant detailed examination. In this study, the individual and combined effects of DIM and DIF on conventional developmental parameters (hatching rate, deformity rate, lethality) and gene expression were measured in embryonic zebrafish. Both DIF and DIM interfered with normal zebrafish embryo development, and the most sensitive toxicity index for both was 96 h post-fertilization (hpf) deformity rate (BMDL10 values of 0.30 and 1.10 mg/L, respectively). The combination of DIF and DIM had mainly synergistic deleterious effects on 96 hpf deformity and mortality rates. Transcriptome analysis showed that these compounds markedly downregulated expression of mcm family genes, cdk1, and cdc20, thereby potentially disrupting DNA replication and cell cycle progression. Enhanced surveillance for this pesticide combination is recommended as simultaneous environmental exposure may be substantially more harmful than exposure to either compound alone.


Assuntos
Dioxolanos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Morfolinas/toxicidade , Triazóis/toxicidade , Peixe-Zebra , Animais , Embrião não Mamífero/anormalidades , Desenvolvimento Embrionário/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Perfilação da Expressão Gênica , Poluentes Químicos da Água/toxicidade
4.
Ecotoxicol Environ Saf ; 217: 112258, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915451

RESUMO

Pathogens and pollutants, such as pesticides, are potential stressors to all living organisms, including honey bees. Herbicides and fungicides are among the most prevalent pesticides in beehive matrices, and their interaction with Nosema ceranae is not well understood. In this study, the interactions between N. ceranae, the herbicide glyphosate and the fungicide difenoconazole were studied under combined sequential and overlapping exposure to the pesticides at a concentration of 0.1 µg/L in food. In the sequential exposure experiment, newly emerged bees were exposed to the herbicide from day 3 to day 13 after emerging and to the fungicide from day 13 to day 23. In the overlapping exposure experiment, bees were exposed to the herbicide from day 3 to day 13 and to the fungicide from day 7 to day 17. Infection by Nosema in early adult life stages (a few hours post emergence) greatly affected the survival of honey bees and elicited much higher mortality than was induced by pesticides either alone or in combination. Overlapping exposure to both pesticides induced higher mortality than was caused by sequential or individual exposure. Overlapping, but not sequential, exposure to pesticides synergistically increased the adverse effect of N. ceranae on honey bee longevity. The combination of Nosema and pesticides had a strong impact on physiological markers of the nervous system, detoxification, antioxidant defenses and social immunity of honey bees.


Assuntos
Abelhas/fisiologia , Dioxolanos/toxicidade , Glicina/análogos & derivados , Nosema/fisiologia , Praguicidas/toxicidade , Triazóis/toxicidade , Animais , Abelhas/microbiologia , Fungicidas Industriais/toxicidade , Glicina/toxicidade , Herbicidas/toxicidade , Glifosato
5.
Food Chem Toxicol ; 152: 112162, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33813062

RESUMO

Difenoconazole, cypermethrin and triazophos are widely used pesticides in agricultural production and frequently detected in foods. The aim of this study was to determine the effect of these pesticides and their mixtures on cell viability, reactive oxygen species (ROS), lactate dehydrogenase (LDH) content, apoptosis rate and DNA fragmentation and synthesis in human hepatocellular carcinoma cells (HepG2). The order of inhibitory effects for the individual pesticides was ranked as difenoconazole > cypermethrin > triazophos. The enhanced expression of caspase-3, caspase-7 and PARP activity was observed in HepG2 cells, which was 1.7, 1.3 and 1.6-fold higher than the control, respectively, along with significant protein cleavage; and induced apoptosis in a concentration-dependent manner. Further, the pesticide mixtures significantly increased ROS level (up to 1.3-fold), induced DNA fragmentation (up to 1.8-fold), inhibited DNA synthesis (up to 53%), and damaged the cells by destroying the cell membrane and producing a large amount of LDH at concentration range of 10-30 µM. Specifically, mixtures containing difenoconazole showed stronger toxicities than individual pesticides, implying higher health risks associated with mixtures. Our results show that three widely used pesticides exhibited cytotoxicity and apoptosis through the ROS-related caspase pathway, providing a basis for evaluation of health risks from pesticide mixtures via food consumption.


Assuntos
Apoptose/efeitos dos fármacos , Dioxolanos/toxicidade , Organotiofosfatos/toxicidade , Praguicidas/toxicidade , Piretrinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Triazóis/toxicidade , Caspase 3/metabolismo , Caspase 7/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , L-Lactato Desidrogenase/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo
6.
Arch Toxicol ; 95(4): 1397-1411, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33575850

RESUMO

The liver is constantly exposed to mixtures of hepatotoxic compounds, such as food contaminants and pesticides. Dose addition is regularly assumed for mixtures in risk assessment, which however might not be sufficiently protective in case of synergistic effects. Especially the prediction of combination effects of substances which do not share a common adverse outcome (AO) might be problematic. In this study, the focus was on the endpoint liver triglyceride accumulation in vitro, an indicator of hepatic fatty acid changes. The hepatotoxic compounds difenoconazole, propiconazole and tebuconazole were chosen which cause hepatic fatty acid changes in vivo, whereas fludioxonil was chosen as a hepatotoxic substance not causing fatty acid changes. Triglyceride accumulation was analyzed for combinations of steatotic and non-steatotic pesticides in human HepaRG hepatocarcinoma cells. Investigations revealed a potentiation of triglyceride accumulation by mixtures of the steatotic compounds with the non-steatotic fludioxonil, as compared to the single compounds. Mathematical modeling of combination effects indicated more than additive effects for the tested combinations if the method by Chou was applied, and a decrease in EC50 values of the steatotic compounds when applied in mixtures. Use of an adverse outcome pathway (AOP)-driven testing strategy for liver steatosis showed interactions of the test compounds with the nuclear receptors AHR, CAR and PXR, as well as a downregulation of ACOX2. An ACOX2-dependent mechanism underlying the observed mixture effect could not be verified using a siRNA approach. By contrast, a toxicokinetic interaction was identified including an inhibition of the metabolic enzyme CYP3A4 by fludioxonil and a decreased metabolic conversion of the CYP3A4 substrate difenoconazole when used in mixture experiments. In conclusion, an interaction by a steatotic and a non-steatotic compound at the toxicokinetic level on the endpoint triglyceride accumulation in vitro was described.


Assuntos
Fígado Gorduroso/induzido quimicamente , Fígado/efeitos dos fármacos , Praguicidas/toxicidade , Triglicerídeos/metabolismo , Rotas de Resultados Adversos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Dioxolanos/administração & dosagem , Dioxolanos/toxicidade , Dioxóis/administração & dosagem , Dioxóis/toxicidade , Ácidos Graxos/metabolismo , Células Hep G2 , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Modelos Teóricos , Pirróis/administração & dosagem , Pirróis/toxicidade , Triazóis/administração & dosagem , Triazóis/toxicidade
7.
Clin Toxicol (Phila) ; 59(2): 101-105, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33191804

RESUMO

INTRODUCTION: Although spices are widely used as food products and are generally regarded as safe, intentional abuse of household spices may occur and is likely underreported in the medical literature. Spices are inexpensive and widely available for purchase by individuals of all ages and may be perceived as being safer than traditional drugs of abuse. DISCUSSION: Nutmeg, cinnamon, and vanilla are commonly abused spices. The major component of nutmeg is myristicin; myristicin has activity at serotonergic receptors and may result in psychomimetic symptoms after exposure. Cinnamon oils contain local irritants which may cause dermatitis or ulcerations after topical application. Ground cinnamon contains cellulose fibers; these are biopersistent and bioresistant, and inhalational exposure to cinnamon powder can result in chronic pulmonary inflammation and fibrosis. Pure vanilla extract contains a minimum of 35% ethanol according to the United States Food and Drug Administration standards, and abuse of vanilla extract may occur among individuals seeking ethanol intoxication. CONCLUSIONS: Overall, misuse or abuse of these spices frequently results in mild to moderate symptoms that do not require medical intervention, although more serious intoxications may require hospitalization. Clinicians should be aware of the potential dangers of household spice abuse and understand management strategies for these exposures.


Assuntos
Cinnamomum zeylanicum/toxicidade , Myristica/toxicidade , Especiarias/toxicidade , Transtornos Relacionados ao Uso de Substâncias/etiologia , Vanilla/toxicidade , Derivados de Alilbenzenos/toxicidade , Dioxolanos/toxicidade , Humanos
8.
Ecotoxicol Environ Saf ; 203: 111013, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888588

RESUMO

Multiple pesticides originating from plant protection treatments and the treatment of pests infecting honey bees are frequently detected in beehive matrices. Therefore, winter honey bees, which have a long life span, could be exposed to these pesticides for longer periods than summer honey bees. In this study, winter honey bees were exposed through food to the insecticide imidacloprid, the fungicide difenoconazole and the herbicide glyphosate, alone or in binary and ternary mixtures, at environmental concentrations (0 (controls), 0.1, 1 and 10 µg/L) for 20 days. The survival of the honey bees was significantly reduced after exposure to these 3 pesticides individually and in combination. Overall, the combinations had a higher impact than the pesticides alone with a maximum mortality of 52.9% after 20 days of exposure to the insecticide-fungicide binary mixture at 1 µg/L. The analyses of the surviving bees showed that these different pesticide combinations had a systemic global impact on the physiological state of the honey bees, as revealed by the modulation of head, midgut and abdomen glutathione-S-transferase, head acetylcholinesterase, abdomen glucose-6-phosphate dehydrogenase and midgut alkaline phosphatase, which are involved in the detoxification of xenobiotics, the nervous system, defenses against oxidative stress, metabolism and immunity, respectively. These results demonstrate the importance of studying the effects of chemical cocktails based on low realistic exposure levels and developing long-term tests to reveal possible lethal and adverse sublethal interactions in honey bees and other insect pollinators.


Assuntos
Abelhas/fisiologia , Fungicidas Industriais/toxicidade , Herbicidas/toxicidade , Inseticidas/toxicidade , Praguicidas/toxicidade , Animais , Dioxolanos/toxicidade , Sinergismo Farmacológico , Glicina/análogos & derivados , Glicina/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Polinização/efeitos dos fármacos , Triazóis/toxicidade , Glifosato
9.
Ecotoxicology ; 29(9): 1486-1499, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32388636

RESUMO

This study evaluated the toxicity of pesticide formulations Kraft® 36 EC (active ingredient-a.i. abamectin) and Score® 250 EC (a.i. difenoconazole), and their mixtures in Daphnia magna at different biological levels of organization. Survival, reproduction and biochemical markers (cholinesterase (ChE), catalase (CAT) and lipid peroxidation (LPO)) were some of the endpoints evaluated. Total proteins and lipids were also studied together with energy consumption (Ec). D. magna neonates were exposed for 96 h to Kraft (2, 4, and 6 ng a.i./L) and Score (12.5, 25, and 50 µg a.i./L) for the biochemical experiments, and for 15 days to abamectin (1-5 ng a.i./L) and to difenoconazole (3.12-50 µg a.i./L) to assess possible changes in reproduction. Exposures of organisms to both single compounds did not cause effects to antioxidant and detoxifying enzymes, except for LPO occurring at the highest concentration of difenoconazole tested. For ChE and CAT there was enzymatic induction in mixture treatments organisms, occurring at minor pesticides concentrations for CAT and at the two highest concentrations for ChE. There were no significant differences for total protein in D. magna but lipids showed an increase at the highest concentrations of pesticide mixture combinations. There was a significant increase of Ec in individuals of all treatments tested. In the chronic test, increased fecundity occurred for D. magna under difenoconazole exposures and mixtures. This study demonstrated that mixtures of these pesticides caused greater toxicity to D. magna than when tested individually, except for Ec. Therefore, effects of mixtures are very hard to predict only based on information from single compounds, which most possibly is the result of biological complexity and redundancy in response pathways, which need further experimentation to become better known.


Assuntos
Daphnia/fisiologia , Dioxolanos/toxicidade , Ivermectina/análogos & derivados , Praguicidas/toxicidade , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Colinesterases , Ivermectina/toxicidade , Reprodução , Testes de Toxicidade Aguda
10.
Ecotoxicol Environ Saf ; 194: 110446, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171122

RESUMO

Pesticides can affect all receiving compartments, especially soils, and their fate and effects may be enhanced by temperature, increasing their risk to ecological functions of soils. In Brazil, the most widely used pesticides are the insecticide Kraft 36 EC® (a.s. abamectin) and the fungicide Score 250 EC® (a.s. difenoconazole), which are commonly used in strawberry, often simultaneously as a mixture. The aim of this study was to evaluate the toxicity of realistic environmental applications, single and in mixtures, for both pesticides to the springtail Folsomia candida and the plant species Allium cepa (onion) and Lycopersicum esculentum (tomato). Mesocosms filled with Brazilian natural soil (lattosolo) were dosed with water (control), Kraft (10.8 g a.s/ha), Score (20 g.a.s/ha) and Kraft + Score (10.8 + 20 g a.s./ha). The applications were repeated every 7 days, during 18 days of experiment, and simulating rainfall twice a week. Collembola reproduction tests were conducted with soils from the first (day 1) and last day (day 18) of experiment for each treatment. Plant toxicity tests were carried out in the experimental units. The experiments were run at 23 °C and 33 °C. Kraft, alone and in the binary mixture, showed high toxicity to the springtails in soils from both days 1 and 18, especially at 23 °C where it caused 100% mortality. Score however, was not toxic to the springtails. Plant growth was reduced by Score, but responses varied depending on temperature. This study indicates a high environmental risk of the insecticide Kraft, particularly at lower temperatures (23 °C), and an influence of temperature on pesticide fate and effects.


Assuntos
Dioxolanos/toxicidade , Ivermectina/análogos & derivados , Poluentes do Solo/toxicidade , Triazóis/toxicidade , Animais , Artrópodes/fisiologia , Brasil , Exposição Ambiental , Fungicidas Industriais , Inseticidas/toxicidade , Ivermectina/toxicidade , Praguicidas/toxicidade , Solo , Temperatura , Testes de Toxicidade
11.
Environ Sci Pollut Res Int ; 26(34): 35253-35265, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701422

RESUMO

Difenoconazole is a fungicide extensively used in agriculture. The aim of this study was to evaluate the effects of difenoconazole fungicide on the sperm quality of rats. Wistar rats were divided into four groups: control and exposed to 5 (D5), 10 (D10), or 50 mg-1 kg bw-1day (D50) of difenoconazole for 30 days, by gavage. Classical sperm parameters and surface-enhanced Raman scattering (SERS) were performed. Progressive motility, acrosomal integrity, and percentage of morphologically normal spermatozoa were reduced in the D10 and D50 groups in comparison with the control group. Sperm viability was reduced only in the D50 group. Sperm number in the testis and caput/corpus epididymis and daily sperm production were reduced in the three exposed groups. SERS measurements showed changes in the spectra of spermatozoa from D50 group, suggesting DNA damage. In addition, machine learning (ML) methods were used to evaluate the performance of three classification algorithms (artificial neural network-ANN, K-nearest neighbors-K-NN, and support vector machine-SVM) in the identification task of the groups exposed to difenoconazole. The results obtained by ML algorithms were very promising with accuracy ≥ 90% and validated the hypothesis of the exposure to difenoconazole reduces sperm quality. In conclusion, exposure of rats to different doses of the fungicide difenoconazole may impair sperm quality, with a recognizable classification pattern of exposure groups.


Assuntos
Dioxolanos/toxicidade , Fungicidas Industriais/toxicidade , Aprendizado de Máquina , Espermatozoides/efeitos dos fármacos , Triazóis/toxicidade , Animais , Dano ao DNA , Epididimo/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Análise Espectral Raman , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Máquina de Vetores de Suporte , Testículo/efeitos dos fármacos , Testes de Toxicidade
13.
Ecotoxicol Environ Saf ; 182: 109375, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299474

RESUMO

The continuous and extensive use of pesticides, particularly in the field of agriculture, leads to contamination of all ecosystems (water, soil, and atmosphere). Among pesticides, fungicides constitute a larger group whose impact on the environment are still poorly studied. Difenoconazole belongs to triazole group of fungicides having high photochemical stability and have low biodegradability, which makes them persistent in water bodies. The present study focuses on the physiological and cytotoxic impact of difenoconazole fungicide on ciliated protozoa, Tetrahymena pyriformis with reference to growth, morphology, behaviour and its generation time. Morphological studies showed changes in the shape and size of T. pyriformis. Our result showed an inhibitory effect on population growth of T. pyriformis and the IC50 concentration was found to be 6.8 µg mL-1.The numbers of generations decreased and generation time was found to be extended in a concentration and time dependent manner. Difenoconazole caused significant depletion in phagocytic activity and also ultra-structural changes were observed by Transmission electron microscopy (TEM) analysis. The results indicate that the Tetrahymena toxicity assay could be used as a complementary system to rapidly elucidate the cytotoxic potential of fungicide.


Assuntos
Dioxolanos/toxicidade , Fungicidas Industriais/toxicidade , Tetrahymena pyriformis , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Tetrahymena pyriformis/efeitos dos fármacos , Tetrahymena pyriformis/fisiologia , Tetrahymena pyriformis/ultraestrutura
14.
Apoptosis ; 24(9-10): 730-744, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31243599

RESUMO

Piperlongumine (PL) is an alkaloid that inhibits glutathione S-transferase pi 1 (GSTP1) activity, resulting in elevated reactive oxygen species (ROS) levels and cancer-selective cell death. We aimed to identify stress-associated molecular responses to PL treatment in pancreatic ductal adenocarcinoma (PDAC) cells. GSTP1 directly interacts with JNK, which is activated by oxidative stress and can lead to decreased cancer cell proliferation and cell death. Therefore, we hypothesized that JNK pathways are activated in response to PL treatment. Our results show PL causes dissociation of GSTP1 from JNK; robust JNK, c-Jun, and early ERK activation followed by suppression; increased expression of cleaved caspase-3 and cleaved PARP; and nuclear translocation of Nrf2 and c-Myc in PDAC cells. Gene expression analysis revealed PL caused a > 20-fold induction of heme oxygenase-1 (HO-1), which we hypothesized was a survival mechanism for PDAC cells under enhanced oxidative stress. HO-1 knockout resulted in enhanced PL-induced PDAC cell death under hypoxic conditions. Similarly, high concentrations of the HO-1 inhibitor, ZnPP (10 µM), sensitized PDAC cells to PL; however, lower concentrations ZnPP (10 nM) and high or low concentrations of SnPP both protected PDAC cells from PL-induced cell death. Interestingly, the JNK inhibitor significantly blocked PL-induced PDAC cell death, Nrf-2 nuclear translocation, and HMOX-1 mRNA expression. Collectively, the results demonstrate JNK signaling contributes to PL-induced PDAC cell death, and at the same time, activates Nrf-2 transcription of HMOX-1 as a compensatory survival mechanism. These results suggest that elevating oxidative stress (using PL) while at the same time impairing antioxidant capacity (inhibiting HO-1) may be an effective therapeutic approach for PDAC.


Assuntos
Apoptose/efeitos dos fármacos , Dioxolanos/farmacologia , Heme Oxigenase-1/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Pancreáticas , Alcaloides/farmacologia , Alcaloides/toxicidade , Linhagem Celular Tumoral/metabolismo , Dioxolanos/toxicidade , Heme Oxigenase-1/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Ativação Transcricional/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Neoplasias Pancreáticas
15.
J Agric Food Chem ; 67(15): 4328-4336, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30912427

RESUMO

Myristicin is widely distributed in spices and medicinal plants. The aim of this study was to explore the role of metabolic activation of myristicin in its potential toxicity through a metabolomic approach. The myristicin- N-acetylcysteine adduct was identified by comparing the metabolic maps of myristicin and 1'-hydroxymyristicin. The supplement of N-acetylcysteine could protect against the cytotoxicity of myristicin and 1'-hydroxymyristicin in primary mouse hepatocytes. When the depletion of intracellular N-acetylcysteine was pretreated with diethyl maleate in hepatocytes, the cytotoxicity induced by myristicin and 1'-hydroxymyristicin was deteriorated. It suggested that the N-acetylcysteine adduct resulting from myristicin bioactivation was closely associated with myristicin toxicity. Screening of human recombinant cytochrome P450s (CYPs) and treatment with CYP inhibitors revealed that CYP1A1 was mainly involved in the formation of 1'-hydroxymyristicin. Collectively, this study provided a global view of myristicin metabolism and identified the N-acetylcysteine adduct resulting from myristicin bioactivation, which could be used for understanding the mechanism of myristicin toxicity.


Assuntos
Compostos de Benzil/metabolismo , Compostos de Benzil/toxicidade , Dioxolanos/metabolismo , Dioxolanos/toxicidade , Hepatócitos/efeitos dos fármacos , Pirogalol/análogos & derivados , Acetilcisteína/química , Acetilcisteína/metabolismo , Ativação Metabólica , Derivados de Alilbenzenos , Animais , Compostos de Benzil/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocromo P-450 CYP1A1/metabolismo , Dioxolanos/química , Hepatócitos/citologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pirogalol/química , Pirogalol/metabolismo , Pirogalol/toxicidade
16.
Environ Pollut ; 244: 342-350, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30352348

RESUMO

Pesticides risk assessments have traditionally focused on the effects on standard parameters, such as mortality, reproduction and development. However, one of the first signs of adverse effects that occur in organisms exposed to stress conditions is an alteration in their genomic expression, which is specific to the type of stress, sensitive to very low contaminant concentrations and responsive in a few hours. The aim of the present study was to evaluate the single and binary mixture toxicity of commercial products of abamectin (Kraft® 36 EC) and difenoconazole (Score® 250 EC) to Folsomia candida. Laboratory toxicity tests were conducted to access the effects of these pesticides on springtail survival, reproduction and gene expression. The reproduction assays gave EC50 and EC10 values, respectively, of 6.3 and 1.4 mg a.s./kg dry soil for abamectin; 1.0 and 0.12 mg a.s./kg dry soil for Kraft® 36 EC; and 54 and 23 mg a.s./kg dry soil for Score® 250 EC. Technical difenoconazole did not have any effect at the concentrations tested. No significant differences in gene expression were found between the abamectin concentrations tested (EC10 and EC50) and the solvent control. Exposure to Kraft® 36 EC, however, significantly induced Cyp6 expression at the EC50 level, while VgR was significantly downregulated at both the EC10 and EC50. Exposure to the simple pesticide mixture of Kraft® 36 EC + Score® 250 EC caused significant up regulation of ABC transporter, and significant down regulation of VgR relative to the controls. GABA receptor also showed significant down-regulation between the EC10 and EC50 mixture treatments. Results of the present study demonstrate that pesticide-induced gene expression effects precede and occur at lower concentrations than organism-level responses. Integrating "omic" endpoints in traditional bioassays may thus be a promising way forward in pesticide toxicity evaluations.


Assuntos
Artrópodes/metabolismo , Dioxolanos/toxicidade , Expressão Gênica/efeitos dos fármacos , Ivermectina/análogos & derivados , Praguicidas/toxicidade , Poluentes do Solo/toxicidade , Triazóis/toxicidade , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Artrópodes/efeitos dos fármacos , Artrópodes/genética , Família 6 do Citocromo P450/genética , Família 6 do Citocromo P450/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Regulação da Expressão Gênica/genética , Ivermectina/toxicidade , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de GABA/genética , Receptores de GABA/metabolismo , Reprodução/efeitos dos fármacos , Solo/química
17.
Chemosphere ; 210: 531-538, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30029145

RESUMO

In recent years, the need for the development of alternative test methods for the conventional acute fish toxicity test (AFT) with adult fish has often been discussed. In addition, concerns have been raised on the potential risks related with environmentally realistic pesticide mixtures since risk evaluations have traditionally been based on individual pesticides. The insecticide/acaricide abamectin and the fungicide difenoconazole are the main pesticides that are intensively used in Brazilian strawberry crop and are hence likely to occur simultaneously in edge-of-field waterbodies. The aim of the present study was therefore to evaluate the lethal and sublethal toxicity of single and mixture exposures of these pesticides to zebrafish early life stages (embryos and juveniles). By comparing the derived toxicity data of the individual compounds with that previously determined for zebrafish adults, the order of life stage sensitivity was juvenile > adult > embryo. The pesticide mixture revealed a dose-level dependent deviation of the independent action model, with antagonism at low dose levels and synergism at high dose levels. Sublethal parameters (especially those related with locomotion) were considerably more sensitive than lethality. Subsequently, the inclusion of sublethal parameters may greatly improve the sensitivity of FET tests and hence its suitability as a substitution of adult fish testing in risk assessment evaluations.


Assuntos
Dioxolanos/toxicidade , Ivermectina/análogos & derivados , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Interações Medicamentosas , Fungicidas Industriais , Inseticidas/farmacologia , Ivermectina/toxicidade , Estágios do Ciclo de Vida/efeitos dos fármacos , Praguicidas/farmacologia , Praguicidas/toxicidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/farmacologia , Peixe-Zebra/crescimento & desenvolvimento
18.
J Environ Sci (China) ; 63: 126-132, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29406096

RESUMO

Difenoconazole (DFZ) is a triazole fungicide which has been detected in the aquatic environment, including estuaries and embayments. However, few studies addressing the reproductive toxicity and transgenerational effects of DFZ on marine fishes are available. The present study was conducted to investigate the effects of DFZ on male marine medaka (Oryzias melastigma). After exposure of the embryo to 1, 10, 100 and 1000ng/L DFZ for 180days, the gonadosomatic index was significantly decreased in the 1000ng/L treatment. The number of sperm was reduced while the abundances of spermatocytes and spermatogonia in the testes were increased in all the treatments. The mRNA levels of salmon-type gnrh (sgnrh), the luteinizing hormone (lhß) and the follicle-stimulating hormone (fshß) genes in the brain all exhibited a significant down-regulation, the expression of androgen receptors (arα and arß) was decreased and that of estrogen receptor ß and cytochrome P450 aromatase (cyp19B) was increased in the testes. The expression levels of cyp19A and cyp19B were increased in the liver. The decrease of ars mRNA levels might be one of the reasons causing the reduction of sperm. The down-regulation of sgnrh, lhß and fshß mRNA levels suggested that DFZ might impact the spermatogenesis via the brain-pituitary-gonad pathway. The decrease of the fertilization success, the hatch ability and the swim-up success in the F1 generation indicated that DFZ pollution at environmental levels might cause a decrease of wild fish populations.


Assuntos
Dioxolanos/toxicidade , Fungicidas Industriais/toxicidade , Oryzias/fisiologia , Triazóis/toxicidade , Animais , Aromatase/metabolismo , Masculino , Receptores Androgênicos , Reprodução/efeitos dos fármacos , Testículo , Poluentes Químicos da Água/toxicidade
19.
Aquat Toxicol ; 194: 112-120, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29175743

RESUMO

Difenoconazole is widely used to inhibit the growth of fungi, but its residue in the water environment may threaten ecosystem and human health. Here, 1H nuclear magnetic resonance (NMR) and LC-MS/MS based metabolomics and transcriptomics approaches were used to assess the response of zebrafish to difenoconazole exposure. Early life stages of zebrafish were exposed to difenoconazole at environmentally relevant concentrations for 168h. Their comparison with the control group suggested an adverse development and disturbance of steroid hormones and VTG. KEGG pathway analysis identified five biological processes on the basis of differentially expressed genes (DEGs), as well as altered metabolites and amino acids in zebrafish following difenoconazole exposure. These affected processes included energy metabolism, amino acids metabolism, lipid metabolism, nucleotide metabolism, and an immune-related pathway. Collectively, these results bring us closer to an incremental understanding of the toxic effects of difenoconazole on zebrafish in its early development, and lend support to the continued use of the early life stages of zebrafish as a classical model to evaluate underlying environmental risks of xenobiotics in aquatic organisms.


Assuntos
Dioxolanos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Distribuição Aleatória
20.
Environ Pollut ; 233: 208-217, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29096293

RESUMO

Difenoconazole, a typical triazole fungicide, inhibits lanosterol-14R-demethylase (CYP51) to prevent fungal sterol synthesis and its residues are frequently detected in the environment due to its wide application. Previous studies have demonstrated that difenoconazole altered the triglyceride levels, and gene expression relevant to cholesterol biosynthesis in zebrafish. However, endocrine-disruption in the hypothalamus-pituitary-gonadal-liver (HPGL) axis, the effects of transferring to offspring, and the underlying mechanisms of difenoconazole in aquatic organisms are still unknown. In this study, we defined the effects of difenoconazole at environmental concentrations on endocrine disturbance using zebrafish as an experimental model. The results indicated that difenoconazole induced a significant change in the somatic index, and pathological variations in tissues, and steroid hormone levels. RT-PCR experiments further confirmed that difenoconazole significantly induced expression alteration of lhr, hsd3ß, hsd11ß, cyp19a in the ovary and star, cyp19a, cyp3c1 in the testis, and erα genes in livers. In addition, difenoconazole exposure in parental zebrafish affected the hatchability and length of its offspring. Moreover, the burdens of difenoconazole and difenoconazole alcohol in females were higher than in males. These findings highlighted that difenoconazole exposure at environmentally relevant concentrations elicited estrogenic endocrine-disruption effects via altering homeostasis of sex steroid hormones in the HPGL axis and the adverse effects can be transferred to the offspring.


Assuntos
Dioxolanos/toxicidade , Disruptores Endócrinos/toxicidade , Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Organismos Aquáticos/metabolismo , Disruptores Endócrinos/metabolismo , Feminino , Fungicidas Industriais/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Fígado/metabolismo , Masculino , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
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