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1.
Chemosphere ; 235: 1116-1124, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561302

RESUMO

The porous graphitic carbon nitride nanosheets (PCNSs) with high yields were synthesized by using one-step chemical exfoliation method. PCNSs accelerated separation efficiency of photo-generated electron-hole pairs in comparison to bulk graphitic carbon nitride. The PCNS5 (exfoliation for 5 h) exhibited optimal photocatalytic disinfection capability towards Escherichia coli K-12 under simulated solar light irradiation with complete disinfection of 6.5 log10 cfu/mL of E. coil K-12 within 2 h. The enhanced photocatalytic activity of PCNS5 originated from mesoporous nanosheet structure. The possible mechanism of photocatalytic disinfection has proposed that intracellular reactive oxygen species levels and the activities of antioxidant enzymes (e.g., catalase and superoxide dismutase) were enhanced. Transmission electron microscope images observed during photocatalytic disinfection process suggested that the cell membrane was regarded as the first target for oxidation, resulting in a faster leakage of cytoplasmic content and finally degradation of DNA leading to bacterial death. Furthermore, the trapping experiment showed that superoxide radical (•O2-) and holes (h+) were responsible for E. coli K-12 disinfection by PCNS5.


Assuntos
Desinfecção/métodos , Escherichia coli K12/efeitos dos fármacos , Nanoestruturas/química , Nitrilos/toxicidade , Fotólise , Bactérias/efeitos dos fármacos , Membrana Celular/metabolismo , Dano ao DNA , Oxirredução , Porosidade , Espécies Reativas de Oxigênio
2.
J Environ Sci Health B ; 54(7): 580-589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31266377

RESUMO

This study aimed to compare the toxicity for fish of two active ingredients (lambda-cyhalothrin-20 g L-1, a pyrethroid, and acetamiprid-15 g L-1, a neonicotinoid) which are components of a commercial insecticide (Acer 35 EC) used in cotton crop in many West African countries. The juveniles of Oreochromis niloticus (4.01 ± 0.34 g, mean body weight) were exposed for 96 h to increasing concentrations of active ingredients (lambda-cyhalothrin and acetamiprid) or a mixture similar to Acer 35 EC (composed by 20 g of chemical compound lambda-cyhalothrin and 15 g of acetamiprid dissolved in 1 L of acetone). The experiments were carried out under controlled conditions in aquaria according to OECD Guidelines. During the experiments, the behavioral responses (loss of balance, color change, hyperactivity, etc.) that usually precede death were observed in exposed fish. Mortalities were recorded in each aquarium and the LC50-96h of each chemical was determined. The LC50-96h obtained were respectively 0.1268, 0.0029, 182.9 and 0.5685 ppm for Acer 35 EC, lambda-cyhalothrin, acetamiprid and mixture. All insecticides used in this study had profound impact on Nile tilapia behavior which may confirm the neurotoxicity of each single active compound as well as of their mixture.


Assuntos
Ciclídeos , Neonicotinoides/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Ciclídeos/fisiologia , Sinergismo Farmacológico , Inseticidas/toxicidade , Dose Letal Mediana , Mortalidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade
3.
Ecotoxicol Environ Saf ; 182: 109420, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299472

RESUMO

Mancozeb (MZ), chlorothalonil (CT), and thiophanate methyl (TM) are pesticides commonly used in agriculture due to their efficacy, low acute toxicity to mammals, and short environmental persistence. Although the toxic effects of these pesticides have been previously reported, studies regarding their influence on the immune system are limited. As such, this study focused on the immunomodulatory effect of MZ, CT, and TM pesticides on macrophage cells. RAW 264.7 cells were exposed to a range of concentrations (0.1-100 µg/mL) of these pesticides. CT exposure promoted an increase in reactive oxygen species (ROS) and nitric oxide (NO) levels. The MTT and ds-DNA assay results demonstrated that MZ, CT, and TM exposure induced macrophage proliferation. Moreover, MZ, CT, and TM promoted cell cycle arrest at S phase, strongly suggesting macrophage proliferation. The levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ) and caspases (caspase 1, 3, and 8) in macrophages exposed to MZ, CT, and TM pesticides increased, whereas the anti-inflammatory cytokine levels decreased. These results suggest that MZ, CT, and TM exert an immunomodulatory effect on the immune system, inducing macrophage activation and enhancing the inflammatory response.


Assuntos
Praguicidas/toxicidade , Animais , Citocinas/metabolismo , Imunomodulação , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Maneb/toxicidade , Óxido Nítrico/metabolismo , Nitrilos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Tiofanato/toxicidade , Testes de Toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Zineb/toxicidade
4.
Adv Mater ; 31(33): e1901965, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31237375

RESUMO

Antibacterial photocatalytic therapy has been reported as a promising alternative water disinfection technology for combating antibiotic-resistant bacteria. Numerous inorganic nanosystems have been developed as antibiotic replacements for bacterial infection treatment, but these are limited due to the toxicity risk of heavy metal species. Organic semiconductor photocatalytic materials have attracted great attention due to their good biocompatibility, chemically tunable electronic structure, diverse structural flexibility, suitable band gap, low cost, and the abundance of the resources they require. An all-organic composite photocatalytic nanomaterial C3 N4 /perylene-3,4,9,10-tetracarboxylic diimide (PDINH) heterostructure is created through recrystallization of PDINH on the surface of C3 N4 in situ, resulting in enhanced photocatalytic efficiency due to the formation of a basal heterostructure. The absorption spectrum of this composite structure can be extended from ultraviolet to near-infrared light (750 nm), enhancing the photocatalytic effect to produce more reactive oxygen species, which have an excellent inactivation effect on both Gram-negative and positive bacteria, while demonstrating negligible toxicity to normal tissue cells. An efficient promotion of infectious wound regeneration in mice with Staphylococcus aureus infected dermal wounds is demonstrated. This all-organic heterostructure shows great promise for use in wound disinfection.


Assuntos
Antibacterianos/química , Imidas/química , Nitrilos/química , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Semicondutores , Animais , Antibacterianos/uso terapêutico , Antibacterianos/toxicidade , Catálise , Sobrevivência Celular , Escherichia coli/efeitos dos fármacos , Feminino , Luz , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Nanoestruturas/química , Nitrilos/uso terapêutico , Nitrilos/toxicidade , Perileno/química , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/uso terapêutico , Porfirinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia
5.
J Insect Sci ; 19(3)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31120492

RESUMO

Chlorothalonil is a broad spectrum chloronitrile fungicide that has been identified as one of the most common pesticide contaminants found in managed honey bees (Hymenoptera: Apidae: Apis mellifera L.), their food stores, and the hive environment. While not acutely toxic to honey bees, several studies have identified potential sublethal effects, especially in larvae, but comprehensive information regarding the impact of chlorothalonil on adults is lacking. The goal of this study was to investigate the effects of exposure to a field relevant level of chlorothalonil on honey bee antiviral immunity and biochemical markers of general and social immunity, as well as macronutrient markers of nutrition and morphological markers of growth and development. Chlorothalonil exposure was found to have an effect on 1) honey bee resistance and/or tolerance to viral infection by decreasing the survival of bees following a viral challenge, 2) social immunity, by increasing the level of glucose oxidase activity, 3) nutrition, by decreasing levels of total carbohydrate and protein, and 4) development, by decreasing the total body weight, head width, and wing length of adult nurse and forager bees. Although more research is required to better understand how chlorothalonil interacts with bee physiology to increase mortality associated with viral infections, this study clearly illustrates the sublethal effects of chlorothalonil exposure on bee immunity, nutrition, and development.


Assuntos
Abelhas/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Fenômenos Fisiológicos da Nutrição Animal , Animais , Criação de Abelhas , Abelhas/crescimento & desenvolvimento , Abelhas/imunologia , Abelhas/virologia , Biomarcadores , Imunidade Inata , Larva/efeitos dos fármacos , Nodaviridae/fisiologia
6.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067723

RESUMO

Plants employ an intricate and dynamic defense system that includes physiological, biochemical, and molecular mechanisms to counteract the effects of herbivorous attacks. In addition to their tolerance to phytotoxins, beet armyworm has quickly developed resistance to deltamethrin; a widely used pyrethroid insecticide in cotton fields. The lethal concentration (LC50) required to kill 50% of the population of deltamethrin to gossypol-fed Spodoptera exigua larvae was 2.34-fold higher than the control group, suggesting a reduced sensitivity as a consequence of the gossypol diet. Piperonyl butoxide (PBO) treatment was found to synergize with deltamethrin in gossypol-fed S. exigua larvae. To counteract these defensive plant secondary metabolites, beet armyworm elevates their production of detoxification enzymes, including cytochrome P450 monooxygenases (P450s). Gossypol-fed beet armyworm larvae showed higher 7-ethoxycoumarin-O-deethylase (ECOD) activities and exhibited enhanced tolerance to deltamethrin after 48 and 72 h when compared to the control. Moreover, gossypol pretreated S. exigua larvae showed faster weight gain than the control group after transferring to a deltamethrin-supplemented diet. Meanwhile, gossypol-induced P450s exhibited high divergence in the expression level of two P450 genes: CYP6AB14 and CYP9A98 in the midgut and fat bodies contributed to beet armyworm tolerance to deltamethrin. Knocking down of CYP6AB14 and CYP9A98, via double-stranded RNAs (dsRNA) in a controlled diet, rendered the larvae more sensitive to the insecticide. These data demonstrate that generalist insects can exploit secondary metabolites from host plants to enhance their defense systems against other toxic chemicals. Impairing this defense pathway by RNA interference (RNAi) holds a potential to eliminate the pest's tolerance to insecticides and, therefore, reduce the required dosages of agrochemicals in pest control.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Spodoptera/genética , Animais , Gossipol/farmacologia , Butóxido de Piperonila/farmacologia , Spodoptera/efeitos dos fármacos
7.
Sci Total Environ ; 681: 435-443, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31112921

RESUMO

Earthworm (Eisenia fetida) metabolomics is a useful indicator of toxicant exposure. Extracts of whole earthworms are most commonly used to measure metabolic perturbations, in addition to coelomic fluid which has been used on a more limited basis. Coelomocytes are free moving cells found within earthworm coelomic fluid, and the potential of this compartment has not been evaluated for its utility in earthworm metabolomics. In this study, earthworms were exposed to 18.5 and 37.0 mg/kg chlorothalonil, a commonly used fungicide that targets glutathione. The metabolic impacts of a 14-day chlorothalonil exposure were assessed using 1H NMR and targeted LC-MS measurements of earthworm, coelomic fluid, and coelomocyte extracts. Coelomic fluid was identified as the most sensitive matrix for measuring the effects of chlorothalonil exposure, where an increase in glutamine levels was the only biomarker observed at both doses. At the high dose, multiblocked-orthogonal partial least squares-discriminant analysis (MB-OPLS-DA) supported increased N-acetylserine and ophthalmic acid levels as additional biomarkers of exposure in coelomic fluid. These perturbations may indicate increased oxidative stress, although no changes in glutathione were observed in any matrix.


Assuntos
Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Animais , Biomarcadores/metabolismo , Metaboloma , Solo/química
8.
Chemosphere ; 230: 384-395, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31112861

RESUMO

Recently, environment contaminants including pesticides, fungicides, mycotoxin and others chemicals have been suggested to be responsible for the decline in the human spermatozoa quality especially motility and the increase in infertility rate. Chlorothalonil is used widely for protection of vegetables and crops because it is a broad spectrum fungicide. It has been reported that chronic occupational exposure to fungicides was associated with poor spermatozoa morphology in young men. The pubertal period is very important for the male reproductive system development due to spermatogonial cell proliferation, the expansion of meiotic and haploid germ cells. Although some investigations have studied the male reproductive toxicity of chlorothalonil, almost no studies focused on spermatogenesis. The aim of our current investigation was to explore the impacts of chlorothalonil on spermatogenesis and the underlying mechanisms. It demonstrates: i) chlorothalonil decreased boar spermatozoa motility in vitro and increased the cell apoptosis; ii) chlorothalonil inhibited mouse spermatogenesis in vivo; iii) chlorothalonil disturbed spermatogenesis through the disruption of estrogen receptor signalling; iv) chlorothalonil disrupted histone methylation and DNA methylation which might be through estrogen signalling pathways. Due to the over use or incorrect use, chlorothalonil might cause serious problems to human health, especially spermatogenesis. Therefore we strongly recommend that greater attention should be paid to this fungicide to minimise its impact on human health especially spermatogenesis.


Assuntos
Metilação de DNA/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Fungicidas Industriais/toxicidade , Histonas/metabolismo , Nitrilos/toxicidade , Receptores Estrogênicos/metabolismo , Espermatogênese/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , Transdução de Sinais , Motilidade Espermática/efeitos dos fármacos , Espermatogênese/genética , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Suínos
9.
Ecotoxicol Environ Saf ; 180: 252-258, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31096128

RESUMO

In the higher tiers of pesticide risk assessment, the Species Sensitivity Distribution (SSD) concept is often used to establish the effect threshold defined as the concentration protecting 95% of the species (Hazardous Concentration 5%, HC5). The toxicity data included in SSDs are normally established using a constant exposure regime. However, the exposure of pesticides in the field is often characterised by a variable exposure regime. Toxicokinetic-toxicodynamic (TKTD) models can be used to extrapolate the toxic effects of a chemical to a specific, time-variable exposure regime. The aim of this paper was to develop Exposure Pattern Specific SSDs (EPS-SSDs) for three insecticides using TKTD models and to compare the HC5 of different exposure patterns with the same time-weighted average concentration to evaluate whether the use of EPS-SSDs would change the outcome of the ecological risk assessment. The EPS-SSDs were developed by estimating TKTD parameters for the compounds chlorpyrifos, imidacloprid and lambda-cyhalothrin using results from standard, 96 h, single species tests. These parameter estimates were used for TKTD modelling to determine toxicity thresholds (e.g. LC10 and LC50) for contrasting exposure patterns after certain evaluation times (4, 10 or 100 days). HC5 values were constructed with TKTD-predicted LC10- and LC50- values for different exposure patterns characterised by similar time-weighted average concentrations. Differences between those HC5 values ranged from a factor 1 to a factor 2.3 for the short evaluation period (4 d). This difference was smaller when using an evaluation period of 10 days instead of 4 days and selecting the TKTD-predicted LC10 instead of TKTD-predicted LC50 based HC5s. For the long term evaluation period (100 d), a maximum difference of a factor of 30 was found.


Assuntos
Inseticidas/toxicidade , Animais , Clorpirifos/toxicidade , Exposição Ambiental , Neonicotinoides/toxicidade , Nitrilos/toxicidade , Nitrocompostos/toxicidade , Piretrinas/toxicidade , Medição de Risco , Especificidade da Espécie
10.
Chemosphere ; 231: 450-456, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146137

RESUMO

The translation control tumor protein (TCTP) is a kind of conservative, common and important molecule, several functions (such as regulating cell cycle, apoptosis and calcium binding) have been reported. However, few academic researches for role of TCTP in insecticides stress were made so far. In this research, Drosophila kc cells treated with different doses of deltamethrin at different times, indicated that the expression of TCTP reached the highest level when the cells were treated with 20 ppm of deltamethrin at 24 h. The results showed that TCTP expression is associated with deltamethrin stress. To investigate the functional relationship between this gene and deltamethrin resistance, RNA interference (RNAi) and cell transfection were utilized. TCTP knockdown significantly reduced the level of resistance of RNAi-treated cells, and the overexpressions of TCTP in Drosophila kc cells conferred a degree of protection against deltamethrin. Flow cytometry data showed increased apoptosis rate of RNAi-treated cells and decreased apoptosis following cell transfection. These results represent the first evidence that TCTP plays an important role in the regulation of deltamethrin resistance. Therefore, this study could help us to elucidate the environmental toxicity of deltamethrin and new target genes associated with resistance.


Assuntos
Inseticidas/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Testes de Toxicidade , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Drosophila , Proteínas de Drosophila/genética , Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/metabolismo , Neoplasias/genética , Interferência de RNA
11.
Environ Sci Pollut Res Int ; 26(18): 18856-18865, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31062243

RESUMO

Deltamethrine (DLM) is a synthetic pyrethroid with broad spectrum activities against acaricides and insects. Widely used for agricultural and veterinary purposes, its human and animal exposure occurs by ingestion of contaminated water and food and leads to serious health problems. Kefir is fermented milk with numerous health favors counting restorative properties of bacterial flora, immune system stimulation, cholesterol reduction, as well as anti-mutagenic and anti-tumor properties. The present study was undertaken to examine the hepatoprotective and antioxidant potential of kefir against DLM toxicity in male Wistar albino rats. DLM-treated animals revealed a significant increase in serum biochemical parameters as well as hepatic protein and lipid oxidations but caused an inhibition in antioxidant enzymes. Additionally, we have observed an increase in hepatocyte DNA damages. This toxic effect was confirmed by histological study. Kefir administration normalized the elevated serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T bilirubin), and cholesterol. It also reduced DLM-induced protein carbonyl (PC) and malondialdehyde (MDA) formations. Furthermore, Kefir treatment restored catalase (CAT) and superoxide dismutase (SOD) activities. The co-treatment as well as the pre-treatment by kefir showed an improvement of oxidative status as well as suppressed inflammation and DNA damages. However, the pre-treatment seems to be the most efficient. Therefore, it could be concluded that kefir is a natural product able to protect against the hepatotoxic effects of DLM by its free radical-scavenging and potent antioxidant activity.


Assuntos
Antioxidantes/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Poluentes Ambientais/toxicidade , Kefir , Nitrilos/toxicidade , Substâncias Protetoras/farmacologia , Piretrinas/toxicidade , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Função Hepática , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
12.
Environ Sci Pollut Res Int ; 26(21): 21629-21640, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129896

RESUMO

Pesticides are capable of increasing risks to the early development of nontarget organisms through oxidative stress. The supplementation of antioxidants could help to modulate the toxic effects of pesticides, but much remains to be understood in the interactions between pesticides and antioxidants in amphibians. In the present study, the embryotoxicity of a widely used pyrethroid, lambda-cyhalothrin (LCT), and the potential effect of α-tocopherol (TOC) on embryos of Xenopus tropicalis were evaluated. Exposure to LCT did not affect the hatch rate, survival, or body length of the embryos. However, environmentally relevant concentrations of LCT could induce significant malformations on the larvae. Exposure to LCT led to a concentration-dependent induction of oxidative stress and cytotoxicity that subsequently resulted in embryotoxicity. During the early developmental stages, vitamin E could work as a powerful protective antioxidant. The LCT-induced overproduction of reactive oxygen species and increased enzymatic activities were fully inhibited by treatment with 1 µg/L TOC. However, only supplementation with 100 µg/L TOC provided partial protection against the morphological changes caused by LCT. The results from the present study suggest that antioxidant vitamin E possesses protective potential against pyrethroid-induced embryotoxicity in amphibian embryos through the prevention of oxidative stress.


Assuntos
Antioxidantes/metabolismo , Inseticidas/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Vitamina E/metabolismo , Xenopus/embriologia , Animais , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/toxicidade
13.
Mater Sci Eng C Mater Biol Appl ; 101: 138-147, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029306

RESUMO

Nanocomposites composed of Ag and γ-Fe2O3 nanoparticles within poly-γ-glutamic acid (γ-PGA) derived amorphous carbon nitride (a-CN) films (Ag + γ-Fe2O3@a-CN) were synthesized by a one-step facile pyrolysis strategy. Transmission electron microscopy analysis shows that Ag and γ-Fe2O3 nanoparticles were obtained in situ and homogeneously dispersed on the a-CN matrix. The average size of nanoparticles was 8.1 nm. The presence of γ-Fe2O3, Ag, and a-CN in the nanocomposite was confirmed by X-ray diffraction analysis, UV-visible absorption spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Ag + γ-Fe2O3@a-CN catalyzed the degradation of methyl orange. This catalyst was also recycled ten times by magnetic separation without any loss in efficiency. Ag + γ-Fe2O3@a-CN exhibited strong antibacterial activity against E. coli and S. aureus. It also exhibited excellent antibacterial activity even after 20 times magnetic recycling. This indicates that this is a promising recyclable antibacterial and catalyst for environmental applications.


Assuntos
Antibacterianos/farmacologia , Compostos Férricos/farmacologia , Nanocompostos/química , Nitrilos/síntese química , Ácido Poliglutâmico/análogos & derivados , Pirólise , Prata/farmacologia , Animais , Compostos Azo/química , Células CHO , Catálise , Cricetinae , Cricetulus , Testes de Sensibilidade Microbiana , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Nitrilos/toxicidade , Espectroscopia Fotoeletrônica , Ácido Poliglutâmico/química , Espectrofotometria Ultravioleta , Análise Espectral Raman , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
14.
Analyst ; 144(10): 3260-3266, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-30982838

RESUMO

We synthesized six 1-oxo-1H-phenalene-2,3-dicarbonitrile (OPD)-based probes with various leaving groups using an arylthioether linker and for the first time identified the probe O-NH2 capable of highly selective detection of glutathione over cysteine/homocysteine in vitro and in vivo based on an aromatic nuclear substitution reaction (SNAr) mechanism. The fluorescence of the probe O-NH2 was quenched because of the photoinduced electron transfer (PET) process, but switched on by a glutathione-triggered specific recognition reaction between the probe O-NH2 and glutathione. The recognition mechanism for glutathione was explored and verified by theoretical calculations and ESI-MS analysis. Using O-NH2 as the probe, the GSH fluorescence images were demonstrated in HeLa cells and the intracellular GSH levels in different imatinib-resistant K562 tumor cells were firstly determined. Further, O-NH2 was utilized to detect glutathione in D. magna and zebrafish embryos. The combined results indicate that O-NH2 can be applied as an effective tool for detecting glutathione in biological investigations.


Assuntos
Corantes Fluorescentes/química , Glutationa/análise , Nitrilos/química , Fenalenos/química , Animais , Linhagem Celular Tumoral , Daphnia , Desenho de Drogas , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Modelos Químicos , Nitrilos/síntese química , Nitrilos/toxicidade , Fenalenos/síntese química , Fenalenos/toxicidade , Espectrometria de Fluorescência/métodos , Peixe-Zebra
15.
Food Chem Toxicol ; 128: 202-211, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30991128

RESUMO

Myclobutanil is a chiral triazole fungicide that is employed worldwide. Although enantiomers have the same physical-chemical properties, they may differ in terms of activity, metabolism, and toxicity. This investigation consisted of in vitro enantioselective metabolism studies that employed a human model to assess the risks of myclobutanil in humans. A LC-MS/MS enantioselective method was developed and validated. The enzymatic kinetic parameters (VMAX, KMapp, and CLINT) determined for in vitro rac-myclobutanil and S-(+)-myclobutanil metabolism revealed enantioselective differences. Furthermore, human CYP450 enzymes did not metabolize R-(-)-myclobutanil. The predicted in vivo toxicokinetic parameters indicated that S-(+)-myclobutanil may be preferentially eliminated by the liver and suffer the first-pass metabolism effect. However, because CYP450 did not metabolize R-(-)-myclobutanil, this enantiomer could reach the systemic circulation and stay longer in the human body, potentially causing toxic effects. The CYP450 isoforms CYP2C19 and CYP3A4 were involved in rac-myclobutanil and S-(+)-myclobutanil metabolism. Although there were differences in the metabolism of the myclobutanil enantiomers, in vitro inhibition studies did not show significant enantioselective differences. Overall, the present investigation suggested that myclobutanil moderately inhibits CYP2D6 and CYP2C9 in vitro and strongly inhibits CYP3A and CYP2C19 in vitro. These results provide useful scientific information for myclobutanil risk assessment in humans.


Assuntos
Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Triazóis/toxicidade , Cromatografia Líquida , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Fungicidas Industriais/farmacocinética , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Nitrilos/química , Nitrilos/farmacocinética , Reprodutibilidade dos Testes , Estereoisomerismo , Espectrometria de Massas em Tandem , Toxicocinética , Triazóis/química , Triazóis/farmacocinética
17.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30915446

RESUMO

The present study was designed to record the effect of λ-cyhalothrin, Bifenthrin, and Glyphosate on the mortality, avoidance behavior, foraging activity, and activity of Acetylcholine esterase (AChE) and Carboxylesterase (CarE) in Neoscona theisi (Walckenaer, 1841). Highest mortality (70%) in N. theisi was recorded against λ-cyhalothrin. However, Glyphosate was found to be least toxic. Spider spent less time on insecticides/herbicide-treated surfaces. Insecticides/herbicide-treated N. theisi consumed less prey than untreated control spiders. Similarly, when N. theisi were offered insecticide/herbicide-treated prey, they consumed significantly less. Increased AChE and CarE activities were recorded in insecticides/herbicide-treated spiders as compared to control group. Total protein contents were less in insecticides/herbicide-treated spiders than control group. The results revealed that λ-cyhalothrin is more harmful to spiders as compared to Bifenthrin and Glyphosate. It is suggested that the effect of all pesticides used in agro-ecosystem on beneficial insects should be evaluated before using them in the fields.


Assuntos
Glicina/análogos & derivados , Nitrilos/toxicidade , Comportamento Predatório/efeitos dos fármacos , Piretrinas/toxicidade , Aranhas/efeitos dos fármacos , Acetilcolinesterase/efeitos dos fármacos , Animais , Agentes de Controle Biológico , Carboxilesterase/efeitos dos fármacos , Glicina/toxicidade , Herbicidas/toxicidade , Moscas Domésticas , Inseticidas/toxicidade , Proteínas/análise , Aranhas/enzimologia , Aranhas/fisiologia
18.
Chem Biodivers ; 16(5): e1800515, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30903802

RESUMO

The purpose of present study was to analyze the chemical composition of the fat body of insects (Tenebrio molitor) and its eventual variation after the application of insecticides. Using the GC/MS technique, the fat body composition of larvae, males and females was analyzed. The insects were stressed with selected insecticides containing cyfluthrin (Cyflok 50EW) and deltamethrin (K-othrine) recommended for this species of insect by insecticides producers and farmers. The effect of these two chemicals on the chemical compounds patterns from fat body of insects was compared. Possible differences in the fat body composition between developmental stages and the sex of insects were also compared. Possible identified compounds included amino acids, carboxylic acids, alcohols, sterols, glycerol and urea. Our results show that the composition of lipids was different depending on the stage of development, the insecticide used and the elapsed time since its application.


Assuntos
Composição Corporal/efeitos dos fármacos , Inseticidas/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Tenebrio/metabolismo , Aminoácidos/análise , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Larva/metabolismo , Masculino , Esteróis/análise , Tenebrio/efeitos dos fármacos , Tenebrio/crescimento & desenvolvimento
19.
Environ Toxicol ; 34(6): 753-759, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30884102

RESUMO

Deltamethrin (DEL) and other synthetic repellents like N,N-diethyl benzamide (DEB), N,N-diethyl phenylacetamide (DEPA), and N,N-diethyl meta toluamide (DEET) are widely used due their high efficacy against mosquitoes. We evaluated the safe dose on exposure to insecticide and insect repellent individually and in combination in Wistar rats. Rats were administrated with individual chemicals DEL, DEB, DEPA, and DEET and in combination of DEL along DEB, DEPA, and DEET. The reduced glutathione and its detoxifying enzymes were significantly increased in DEL treated rats. Serotonin, dopamine, and noradrenaline were increased in DEL alone and its combination groups. Histopathology revealed that DEL and along with other insect repellants can cause lung toxicities. This study suggests that DEL in combination with other insect repellents showed antagonistic effect against oxidative stress, and there was no significant toxicological effect in the combination groups. The insect repellents with DEL cause less toxic effect and is safe for use.


Assuntos
Repelentes de Insetos/toxicidade , Inseticidas/toxicidade , Neurotransmissores/metabolismo , Nitrilos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Piretrinas/toxicidade , Animais , Antioxidantes/metabolismo , Sinergismo Farmacológico , Feminino , Repelentes de Insetos/administração & dosagem , Inseticidas/administração & dosagem , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Nitrilos/administração & dosagem , Piretrinas/administração & dosagem , Ratos , Ratos Wistar
20.
Sci Total Environ ; 653: 1426-1434, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30759581

RESUMO

Deltamethrin (Del), an important broad-spectrum insecticide, is widely used in agricultural activities. However, Del is an effective reactive oxygen species (ROS) inducer that induces oxidative stress damage in cells or tissues. Del is significantly more toxic to aquatic organisms, especially crustaceans, than to mammals and birds. This study was designed to evaluate the protective effect of melatonin (MT) on the toxicity-induced damage of Del after 6 h in Eriocheir sinensis. The results showed that Del exposure significantly induced oxidative damage in the hepatopancreas and mitochondria, with malondialdehyde (MDA) and glutathione (GSH) levels being significantly increased and superoxide dismutase (SOD) activity being significantly decreased. Moreover, Del exposure significantly induced functional damage of the hepatopancreas and mitochondria, with a significant increase in alanine aminotransferase (ALT), aspartate aminotransferase (AST), acid phosphatase (ACP) and alkaline phosphatase (AKP) activities in the hepatopancreas and the ratio of albumin/globulin (ALB/GLB) in serum, which indicated the permeability and integrity of the membranes were damaged and had caused cell damage. In addition, ATP content, Na+-K+-ATPase activity and cytochrome C (Cyt­C) content in mitochondria decreased significantly, which indicated that Del exposure destroyed the normal respiratory chain of mitochondria. We also evaluated the hematological parameters. Although there were no significant differences in total hemocyte count (THC) levels, hemocyte apoptosis was significantly induced by Del exposure, and the hemocyte phagocytic activity and the hemocyanin levels decreased significantly with Del exposure. However, MT pretreatment not only prevented oxidative damage and functional damage caused by Del exposure to the hepatopancreas and mitochondria, but it also restored the hemocyte apoptotic rate and phagocytic activity to normal levels. In short, Del exposure caused significant oxidative and functional damage to the hepatopancreas, mitochondria and hemocytes of E. sinensis, whereas the use of MT almost completely eliminated the damage caused by Del exposure.


Assuntos
Braquiúros/efeitos dos fármacos , Inseticidas/toxicidade , Melatonina/farmacologia , Nitrilos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Piretrinas/toxicidade , Fosfatase Ácida/metabolismo , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Braquiúros/imunologia , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Hepatopâncreas/patologia , Sistema Imunitário/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
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