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1.
Ann Agric Environ Med ; 27(3): 368-373, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32955216

RESUMO

INTRODUCTION: Chlorpyrifos (CPF) is a organophosphate insecticide widely used in agriculture with attendant adverse health outcomes. Chronic exposure to CPF induces oxidative stress and elicits harmful effects, including hepatic dysfunction. Molecular hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. OBJECTIVE: The aim of this study was to determine whether the intake of hydrogen-rich water (HRW) could protect rats from hepatotoxicity caused by sub-chronic exposure to CPF. MATERIAL AND METHODS: Rats were treated with hydrogen-rich water by oral intake for 8 weeks. Biochemical indicators of liver function, SOD and CAT activity, GSH and MDA levels were determined by the spectrophotometric method. Liver cell damage induced by CPF was evaluated by histopathological and electron microscopy analysis. PCR array analysis was performed to investigated the effects of molecular hydrogen on the regulation of oxidative stress related genes. RESULTS: Both the hepatic function tests and histopathological analysis showed that the liver damage induced by CPF could be ameliorated by HRW intake. HRW intake also attenuated CPF induced oxidative stress, as evidenced by restored SOD activities and MDA levels. The results of PCR Array identified 12 oxidative stress-related genes differentially expressed after CPF exposure, 8 of chich, including the mitochondrial Sod2 gene, were significantly attenuated by HRW intake. The electron microscopy results indicated that the mitochondrial damage caused by CPF was alleviated after HRW treatment. CONCLUSIONS: The results obtained suggest that HRW intake can protect rats from CPF induced hepatotoxicity, and the oxidative stress signaling and the mitochondrial pathway may be involved in the protection of molecular hydrogen.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Clorpirifos/toxicidade , Hidrogênio/farmacologia , Inseticidas/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Relação Dose-Resposta a Droga , Masculino , Estresse Oxidativo/genética , Ratos , Ratos Wistar
2.
Ecotoxicol Environ Saf ; 205: 111344, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32977283

RESUMO

Rotenone is an insecticide that generates oxidative stress in the CNS and induces locomotor dysfunction and neurodegeneration in rodents. Biochanin A [BioA] is an isoflavone with antioxidant and anti-inflammatory actions. The antioxidant and the modulatory action of BioA on PI3K/Akt/mTOR signaling and autophagy were tested in rotenone-Parkinsonian mice. Mice were allocated into; Group I: oil control group, Group II: rotenone group [1-mg/kg/48h, subcutaneously], group III: rotenone and BioA [10-mg/kg]. Rotenone injection resulted in locomotor disturbances in mice, degeneration in dopaminergic neurons [tyrosine hydroxylase-immunoreactive cells], low striatal dopamine, increased malondialdehyde and decreased level of glutathione. Neuroinflammation was evidenced by upregulation of astrocytes [glia fibrillary acidic protein, GFAP] and elevated levels of cytokines. The phosphorylation of PI3K/Akt/mTOR and the autophagy-related protein, beclin-1, were decreased significantly as indicated by Western blot analysis. BioA treatment enhanced locomotor activity and afforded nigral neuroprotection. The mechanism by which BioA produced this effect includes increased antioxidant defenses, lessened proinflammatory cytokines, increased phosphorylation of PI3K/Akt/mTOR proteins and upregulated beclin-1. Importantly, BioA suppressed the striatal astrocyte marker [GFAP]. Overall, the currents study highlighted that BioA activates PI3K/Akt/mTOR signaling and enhances beclin-1 leading to neuroprotection for nigral dopaminergic neurons.


Assuntos
Genisteína/farmacologia , Inseticidas/toxicidade , Fármacos Neuroprotetores/farmacologia , Rotenona/toxicidade , Animais , Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Citocinas/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Glutationa/metabolismo , Masculino , Camundongos , Síndromes Neurotóxicas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
3.
Chemosphere ; 258: 127362, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947664

RESUMO

Neonicotinoids have been described as toxic to bees. In this context, the A. mellifera foragers were exposed to a sublethal concentration of thiamethoxam (LC50/100: 0,0227 ng de thiamethoxam/µL-1 diet), a neurotoxic insecticide, for 8 days; and it was decided to investigate the insecticide effect on the brain by a shotgun proteomic approach followed by label-free quantitative-based proteomics. A total of 401 proteins were identified in the control group (CG); and a total of 350 proteins in the thiamethoxam exposed group (TMX). Quantitative proteomics data showed up 251 proteins with significant quantitative values in the TMX group. These findings demonstrated the occurrence of shared and unique proteins with altered expression in the TMX group, such as ATP synthase subunit beta, heat shock protein cognate 4, spectrin beta chain-like, mushroom body large-type Kenyon cell-specific protein 1-like, tubulin alpha-1 chain-like, arginine kinase, epidermal growth factor receptor, odorant receptor, glutamine synthetase, glutamate receptor, and cytochrome P450 4c3. Meanwhile, the proteins that were expressed uniquely in the TMX group are involved mainly in the phosphorylation, cellular protein modification, and cell surface receptor signalling processes. Interaction network results showed that identified proteins are present in five different metabolic pathways - oxidative stress, cytoskeleton control, visual process, olfactory memory, and glutamate metabolism. Our scientific outcomes demonstrated that a sublethal concentration of thiamethoxam can impair biological processes and important metabolic pathways, causing damage to the nervous system of bees, and in the long term, can compromise the nutrition and physiology of individuals from the colony.


Assuntos
Abelhas/fisiologia , Encéfalo/efeitos dos fármacos , Inseticidas/toxicidade , Tiametoxam/toxicidade , Animais , Memória , Neonicotinoides , Nitrocompostos , Oxazinas , Proteômica , Tiazóis
4.
Chemosphere ; 254: 126779, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957265

RESUMO

Pyrethroids are a class of highly effective, broad-spectrum, less toxic, biodegradable synthetic pesticides. However, despite the extremely wide application of pyrethroids, there are many problems, such as insecticide resistance, lethal/sub-lethal toxicity to mammals, aquatic organisms or other beneficial organisms. The objectives of this review were to cover the main structures, synthesis, steroisomers, mechanisms of action, anti-mosquito activities, resistance, photodegradation and toxicities of pyrethroids. That was to provide a reference for synthesizing or screening novel pyrethroids with low insecticide resistance and low toxicity to beneficial organisms, evaluating the environmental pollution of pyrethroids and its metabolites. Besides, pyrethroids are mainly used for the control of vectors such as insects, and the non-target organisms are mammals, aquatic organisms etc. While maintaining the insecticidal activity is important, its toxic effects on non-target organisms should be also considered. Pyrethroid resistance is present not only in insect mosquitoes but also in environmental microorganisms, which results in anti-pyrethroids resistance (APR) strains. Besides, photodegradation product dibenzofurans is harmful to mammals and environment. Additionally, pyrethroid metabolites may have higher hormonal interference than the parents. Particularly, delivery of pyrethroids in nanoform can reduce the discharge of more toxic substances (such as organic solvents, etc.) to the environment.


Assuntos
Inseticidas/toxicidade , Piretrinas/toxicidade , Animais , Culicidae/efeitos dos fármacos , Resistência a Inseticidas/fisiologia , Inseticidas/química , Inseticidas/metabolismo , Mosquitos Vetores , Fotólise , Piretrinas/química , Piretrinas/metabolismo
5.
Ecotoxicol Environ Saf ; 203: 111046, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888614

RESUMO

Agricultural pesticides serve as effective controls of unwanted weeds and pests. However, these same chemicals can exert toxic effects in non-target organisms. To determine chemical modes of action, the toxicity ratio (TR) and critical body residues (CBRs) of 57 pesticides were calculated for Daphnia magna. Results showed that the CBR values of inert compounds were close to a constant while the CBR values of pesticides varied over a wider range. Although herbicides are categorized as specifically-acting compounds to plants, herbicides did not exhibit excess toxicity to Daphnia magna and were categorized as inert compounds with an average logTR = 0.41, which was less than a threshold of one. Conversely, fungicides and insecticides exhibited strong potential for toxic effects to Daphnia magna with an average logTR >2. Many of these chemicals act via disruption of the nervous, respiratory, or reproductive system, with high ligand-receptor binding activity which leads to higher toxicity for Daphnia magna. Molecular docking using acetylcholinesterase revealed that fungicides and insecticides bind more easily with the biological macromolecule when compared with inert compounds. Quantitative structure-activity relationship (QSAR) analysis revealed that the toxicity of fungicides was mainly dependent upon the heat of formation and polar surface area, while the toxicity of insecticides was more related to hydrogen-bond properties. This comprehensive analysis reveals that there are specific differences in toxic mechanisms between fungicides and insecticides. These results are useful for determining relative risk associated with pesticide exposure to aquatic crustaceans, such as Daphnia magna.


Assuntos
Daphnia/efeitos dos fármacos , Modelos Biológicos , Praguicidas/química , Praguicidas/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Ligação de Hidrogênio , Inseticidas/química , Inseticidas/toxicidade , Simulação de Acoplamento Molecular , Resíduos de Praguicidas/metabolismo , Relação Quantitativa Estrutura-Atividade
6.
Bull Environ Contam Toxicol ; 105(4): 582-587, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32948914

RESUMO

Oreochromis niloticus was exposed to 10.0 ppb of organophosphate insecticide chlorpyrifos (CPF) and avermectin insecticides abamectin (ABM) and emamectin benzoate (EB) for 48 and 96 h. RBC and Hb decreased in CPF- and ABM-exposed fish after 96-h. Plasma ALT, AST, cortisol, and glucose increased in 96-h CPF-, ABM- and EB-exposed fish, while plasma ions declined in 96-h CPF-exposed ones. Insecticides caused alterations in liver oxidative stress parameters. In fish exposed to CPF, CAT increased after 48-h whereas it decreased after 96-h. Also, CAT declined in 48- and 96-h ABM-exposed fish, whereas it elevated in 48-h EB-exposed ones. Insecticides caused decreases in SOD at 48- and 96-h and in GR after 96-h. GSH elevated in CPF-exposed fish after 48-h, while it decreased in all the tested insecticide exposures after 96-h. Malondialdehyde of fish exposed to insecticides for 96-h increased. Consequently, toxic effects of insecticides on O. niloticus were generally as CPF > ABM > EB.


Assuntos
Clorpirifos/toxicidade , Ciclídeos , Inseticidas/toxicidade , Ivermectina/análogos & derivados , Poluentes Químicos da Água/toxicidade , Animais , Análise Química do Sangue/veterinária , Testes Hematológicos/veterinária , Ivermectina/toxicidade , Fígado/efeitos dos fármacos , Fígado/enzimologia , Oxirredução , Distribuição Aleatória , Testes de Toxicidade Aguda/veterinária
7.
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
8.
Ecotoxicol Environ Saf ; 203: 110980, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888623

RESUMO

Pesticides can enter aquatic environments potentially affecting non-target organisms. Unfortunately, the effects of such substances are still poorly understood. This study investigated the effects of the active neonicotinoid substance thiacloprid (TH) and the commercial product Calypso 480 SC (CA) (active compound 40.4% TH) on Mytilus galloprovincialis after short-term exposure to sublethal concentrations. Mussels were tested for seven days to 0, 1, 5 and 10 mg L-1 TH and 0, 10, 50 and 100 mg L-1 CA. For this purpose, several parameters, such as cell viability of haemocytes and digestive cells, biochemical haemolymph features, superoxide dismutase (SOD) and catalase (CAT) enzymatic activity of gills and digestive gland, as well as histology of such tissues were analysed. The sublethal concentrations of both substances lead to abatement or completely stopping the byssal fibres creation. Biochemical analysis of haemolymph showed significant changes (P < 0.01) in electrolytes ions (Cl-, K+, Na+, Ca2+, S-phosphor), lactate dehydrogenase (LDH) enzyme activity and glucose concentration following exposure to both substances. The TH-exposed mussels showed significant imbalance (P < 0.05) in CAT activity in digestive gland and gills. CA caused significant decrease (P < 0.05) in SOD activity in gills and in CAT activity in both tissues. Results of histological analyses showed severe damage in both digestive gland and gills in a time- and concentration-dependent manner. This study provides useful information about the acute toxicity of a neonicotinoid compound and a commercial insecticide on mussels. Nevertheless, considering that neonicotinoids are still widely used and that mussels are very important species for marine environment and human consumption, further researches are needed to better comprehend the potential risk posed by such compounds to aquatic non-target species.


Assuntos
Brânquias/efeitos dos fármacos , Hemolinfa/efeitos dos fármacos , Inseticidas/toxicidade , Mytilus/efeitos dos fármacos , Neonicotinoides/toxicidade , Tiazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Brânquias/enzimologia , Hemócitos/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda
9.
Pestic Biochem Physiol ; 170: 104699, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980057

RESUMO

The resistance to dieldrin gene (Rdl) encodes a subunit of the insect γ-amino butyric acid (GABA) receptor, and the encoded Rdl subunit is a major target site for cyclodiene and phenylpyrazole insecticides. Since the substitution of a single amino acid (Ala to Ser/Gly at position 302) of the Drosophila melanogaster Rdl gene was first identified to confer high level resistance to dieldrin, mutations at the equivalent positions have been reported to confer resistance to dieldrin and/or fipronil in a wide range of different insects. In the cotton bollworm Helicoverpa armigera, there are two Rdl homologs (HaRdl-1 and HaRdl-2) in close proximity on the Z chromosome, which as wild-type sequences, encode alanine and serine respectively at amino acid position 302. In the present study, we used the CRISPR/Cas9 gene editing approach to knock out HaRdl-1 and HaRdl-2 and establish two homozygous knockout strains (ΔRdl-1 and ΔRdl-2). The ΔRdl-1 strain showed low levels of resistance (8.0- to 9.3-fold) to three cyclodiene insecticides (endosulfan, aldrin and dieldrin) compared with the background SCD strain. In contrast, toxicity of the three cyclodiene insecticides to the ΔRdl-2 strain increased significantly (3.6- to 6.3-fold) when compared with the SCD strain. Genetic analysis indicated the obtained resistance to endosulfan and dieldrin in the ΔRdl-1 strain was sex-linked, which is consistent with the fact that HaRdl-1 locus is located on the Z chromosome. The above results demonstrate that both HaRdl-1 and HaRdl-2 are important determinants for the susceptibility of H. armigera SCD strain to the three cyclodiene insecticides, but have opposite effects. It was also found that HaRdl-1 and HaRdl-2 are involved, to some extent, in mediating sensitivity of H. armigera to avermectin and fipronil respectively. We speculate that the HaRdl-1 and HaRdl-2 subunits have different pharmacological properties, which contribute to the differential sensitivities of H. armigera to the tested cyclodienes and other insecticides.


Assuntos
Proteínas de Drosophila/genética , Inseticidas/farmacologia , Inseticidas/toxicidade , Mariposas/genética , Animais , Dieldrin/toxicidade , Drosophila melanogaster/genética , Resistência a Inseticidas/efeitos dos fármacos , Resistência a Inseticidas/genética , Receptores de GABA/genética , Receptores de GABA-A/genética , Genética Reversa
10.
Pestic Biochem Physiol ; 170: 104686, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980070

RESUMO

New insecticides are urgently needed for the control of arthropod vectors of public health diseases. As resistance to many insecticides used for the control of public health pests is ubiquitous, all available chemistries should be evaluated for their potential to effectively control both insecticide-susceptible and insecticide-resistant strains of mosquitoes. This study aimed to evaluate p-p'-difluoro-diphenyl-trichloroethane (DFDT) as a mosquito control technology and relate its activity to that of DDT. We found that topical DFDT was significantly less toxic than DDT to both pyrethroid-susceptible and pyrethroid-resistant strains of Anopheles gambiae and Aedes aegypti. Direct nervous system recording from Drosophila melanogaster CNS demonstrated that DFDT is approximately 10-times less potent than DDT at blocking nerve firing, which may explain its relatively lower toxicity. DFDT was shown to be at least 4500 times more vapor-active than DDT, with an LC50 in a vapor toxicity screening assay of 2.2 µg/cm2. Resistance to DFDT was assessed in two mosquito strains that possess target-site mutations in the voltage-gated sodium channel and upregulated metabolic activity. Resistance ratios for Akdr (An. gambiae) and Puerto Rico (Ae. aegypti) strains were 9.2 and 12.2, respectively. Overall, this study demonstrates that DFDT is unlikely to be a viable public health vector control insecticide.


Assuntos
Aedes/efeitos dos fármacos , Inseticidas/farmacologia , Inseticidas/toxicidade , Piretrinas/toxicidade , Animais , Compostos de Bifenilo , DDT/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/genética , Resistência a Inseticidas/efeitos dos fármacos , Mosquitos Vetores , Porto Rico , Tricloroetanos
11.
Pestic Biochem Physiol ; 170: 104703, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980071

RESUMO

For the last decade, scientists have reported a loss of honeybee colonies. Multiple factors like parasites, pathogens and pesticides are dealt as possible drivers of honeybee losses. In particular, insecticides are considered as a major factor of pollinator poisoning. We applied sublethal concentrations of four insecticidal substances to honeybee larval food and analyzed the effects on transcriptome. The aim was to identify candidate genes indicating early negative impacts after application of insecticidal substances. Honeybee larvae were kept in-vitro under hive conditions (34-35 °C) and fed with dimethoate, fenoxycarb, chlorantraniliprole and flupyradifurone in sublethal concentrations between day 3-6 after grafting. Larvae at day 4, 6 and 8 were sampled and their transcriptome analyzed. By use of a RT-qPCR array differences in gene expression of selected gene families (immune system, development detoxification) were measured. Targets mainly involved in development, energy metabolism and the immune system were significantly affected by the insecticidal substances tested, selectively inducing genes of the detoxification system, immune response and nutritional stress.


Assuntos
Inseticidas/farmacologia , Inseticidas/toxicidade , Animais , Abelhas/genética , Dimetoato , Larva/genética , RNA Mensageiro/genética , Transcriptoma
12.
Pestic Biochem Physiol ; 170: 104682, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980072

RESUMO

To evaluate whether the development of ß-cypermethrin resistance in Blattella germanica (L.) (Blattaria: Blattellidae) affects the fecundity fitness of this insect and to determine the underlying mechanism, we compared fecundity differences between ß-cypermethrin-resistant (R) and sensitive (S) strains of B. germanica, observed the physiological structural changes of ovaries from an visual perspective, and analyzed differences in the ovarian proteome using proteomic methods. The results showed that, compared with the S strain of B. germanica, the R strain of B. germanica had a significantly higher ootheca shedding rate, a significantly lower number of hatched and surviving nymphs, a significantly higher female proportion in the population and defective ovarian development. Ovarian proteomic analysis showed a total of 64 differentially expressed proteins in the R strain, including 18 upregulated proteins and 46 downregulated proteins. Twenty-four significantly differentially expressed proteins were further studied, and 14 were successfully identified, which were mainly classified into the following categories: immunity-related proteins, development-related proteins, structural proteins, energy metabolism-related proteins and proteins with unknown functions. The differential expression of these proteins reflects the overall changes in cell structure and metabolism associated with ß-cypermethrin resistance and explains the possible molecular mechanism of fecundity fitness disadvantages. In summary, ß-cypermethrin resistance can cause fecundity fitness disadvantages in B. germanica. The metabolic deviations needed to overcome the adverse effects of insecticides may result in an energy exchange that affects energy allocation and, ultimately, the basic needs of the insect. The fitness cost due to insecticide resistance is critical to the delay of the evolution of resistance.


Assuntos
Blattellidae/genética , Inseticidas/farmacologia , Inseticidas/toxicidade , Animais , Feminino , Fertilidade/efeitos dos fármacos , Resistência a Inseticidas/efeitos dos fármacos , Resistência a Inseticidas/genética , Proteoma , Proteômica , Piretrinas
14.
Ecotoxicol Environ Saf ; 205: 111340, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32966934

RESUMO

The increase in pesticide use in response to agricultural demands poses a risk to non-target organisms, including fish. Integrated analysis of biochemical, histopathological and genetic parameters in fish exposed to Malathion insecticide provide information on the toxicity mechanisms of this pesticide, which is classified as a probable carcinogen for humans. The present study assessed the biological responses of Colossoma macropomum after exposure to Malathion. We started determining the lethal concentration, which is the concentration capable of killing 50% of the subjects in an acute toxicity test (LC50-96 h), which was 15.77 ± 3.30 mgL-1. The fish were, then, exposed to Malathion during 96 h at a sublethal concentration, 7.30 mgL-1. Overall, we observed an increased activity of biotransformation and antioxidant enzymes, which reduced production of mitochondrial reactive oxygen species after 96 h exposure, as well as kept constant the mitochondrial respiration, Acetylcholinesterase activity and DNA damage. However, fish exposed to insecticide presented severe gill histopathological damage and increased expression of proto-oncogene ras. Taken together, the results suggest that, after four days of exposure to the Malathion, C. macropomum efficiently activates its defense mechanisms, suggesting that the basal response mechanisms are responsive. On the other hand, histopathologic damages evidenced the adverse effects of Malathion on fish, since it promoted gill necrosis and increased the expression of ras oncogene that is directly related to tumorigenesis events.


Assuntos
Antioxidantes/metabolismo , Caraciformes/metabolismo , Dano ao DNA , Inseticidas/toxicidade , Malation/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Caraciformes/genética , Brânquias/efeitos dos fármacos , Brânquias/patologia , Dose Letal Mediana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade Aguda
15.
Ecotoxicol Environ Saf ; 202: 110942, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800224

RESUMO

Spinetoram (XDE-175-J/L), a new spinosyn-based insecticide, is one of the most widely used bio-pesticide worldwide and its registration for direct application on cauliflower to control Plutella xylostella is currently under review in China. In this study, an accredited method for simultaneous determination of spinetoram and its two metabolites in cauliflower was established and validated using QuEChERS (quick, easy, cheap, effective, rugged, and safe) preparation coupled with ultra-liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The average recoveries using this method were ranged from 74 to 99% with relative standard deviations (RSDs) of 2.4-10.5%. The dissipation kinetics and terminal residues of spinetoram and its two metabolites in cauliflower were studied in Tianjin and Guizhou over two years under open field conditions. The dissipation experiments revealed that spinetoram was swiftly degraded in cauliflower, with the half-lives less than or equal to 4.85 days. The terminal residues of total spinetoram (sum of spinetoram and its two metabolites) detected in cauliflower samples were in the range of 0.009 mg/kg-0.337 mg/kg. Dietary risk assessment study was implemented based on the scientific data of field trials, food consumption and acceptable daily intake (ADI). The estimated long-term dietary risk probability (RQ) of total spinetoram from cauliflower was between 5.79% and 5.91%, indicating that spinetoram was associated with acceptable risk for dietary cauliflower consumption. The results would provide scientific guidance for proper usage of spinetoram in cauliflower field ecosystem.


Assuntos
Brassica/fisiologia , Inseticidas/toxicidade , Macrolídeos/toxicidade , China , Cromatografia Líquida/métodos , Dieta , Ecossistema , Inseticidas/análise , Cinética , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas em Tandem/métodos
16.
Ecotoxicol Environ Saf ; 202: 110914, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800249

RESUMO

Bombyx mori(Linnaeus, 1758) is an important economical insect, and the sericulture is a flourishing industry in many developing countries. Pyriproxyfen, a juvenile hormone pesticide, is often applied to cultivations widely in the world, and its exposure often resulted in silk yield reduction and non-cocooning. However, the effect of pyriproxyfen exposure on cocooning and gene expression level in the silk gland of B. mori has not been studied yet, and this study focused on the above issues. The result indicated that pyriproxyfen exposure can lead to silk gland injury, reduction of silk yield and cocooning rate. Furthermore, the expression levels of silk protein synthesis related genes were down regulated significantly. The same change trends were shown between PI3K/Akt and CncC/Keap1 pathway, which is the expressions of key genes can be elevated by pyriproxyfen exposure. In addition, the activity of detoxification enzymes (P450, GST and CarE) and the expression levels of detoxification genes were elevated after pyriproxyfen exposure, suggesting that detoxification enzymes may play an important role in detoxification of pyriproxyfen in silk gland. These results provided possible clues to the silk gland injury and gene transcriptional level changes in silkworm after pyriproxyfen exposure.


Assuntos
Bombyx/fisiologia , Inseticidas/toxicidade , Piridinas/toxicidade , Animais , Bombyx/efeitos dos fármacos , Bombyx/genética , Regulação para Baixo , Proteínas de Insetos/genética , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Larva/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Biossíntese de Proteínas , Seda/biossíntese , Seda/genética , Seda/metabolismo
17.
Ecotoxicol Environ Saf ; 203: 110998, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32778532

RESUMO

Relative ecotoxicity of approved neonicotinoids (i.e. imidacloprid, clothianidin, acetamiprid, thiacloprid, thiamethoxam and dinotefuran) and diamides (i.e. chlorantraniliprole, cyantraniliprole and flubendiamide) was examined on population growth parameters of Zygogramma bicolorata Pallister on parthenium under laboratory conditions at 27 ± 1 °C, 65 ± 5% relative humidity and 10 L : 14D photoperiod. The dose of all tested insecticides in the bioassay procedure was within a minimum range of their recommended field rate. In acute toxicity trial, imidacloprid caused highest rate of mortality in treated adults of Z. bicolorata, however, it was lowest in flubendiamide treatment followed by cyantraniliprole and chlorantraniliprole. Further, based on toxicity coefficient (E) value in acute toxicity trial, all were classified as harmful (H) and diamides were classified as moderately harmful (MH) as per IOBC classification. Moreover, chronic toxicity trials were carried out through life table response experiments (LTREs) in the F1 progeny of acute toxicity experienced group. Prolonged development with the highest mortality was evident in as compared to diamides. Furthermore, population growth parameters i.e. potential fecundity (Pf), natality rate (mx), intrinsic rate of increase (rm), net reproductive rate (R0) and finite rate of increase (λ) was greatly reduced in Z. bicolorata treated with neonicotinoids as compared with diamides. However, mean generation time (Tc), corrected generation time (τ) and the doubling time (DT) was prolonged in neonicotinoids followed by diamides. Furthermore, proportion of females was greatly reduced (0.43-0.48 females) in neonicotinoids as comparison to diamides (0.53-0.55 females) and control (0.67 females). On the basis of ecotoxicity trials, the tested neonicotinoids were highly toxic to Z. bicolorata than diamides. Therefore, diamide insecticides could be used with Z. bicolorata, however, for validation experimentation need to be done under natural field conditions.


Assuntos
Besouros/efeitos dos fármacos , Diamida/toxicidade , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Animais , Besouros/fisiologia , Ecotoxicologia , Feminino , Crescimento Demográfico , Testes de Toxicidade Aguda
18.
Proc Biol Sci ; 287(1932): 20200935, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32752985

RESUMO

Sulfoxaflor is a globally important novel insecticide that can have negative impacts on the reproductive output of bumblebee (Bombus terrestris) colonies. However, it remains unclear as to which life-history stage is critically affected by exposure. One hypothesis is that sulfoxaflor exposure early in the colony's life cycle can impair larval development, reducing the number of workers produced and ultimately lowering colony reproductive output. Here we assess the influence of sulfoxaflor exposure on bumblebee larval mortality and growth both when tested in insolation and when in combination with the common fungal parasite Nosema bombi, following a pre-registered design. We found no significant impact of sulfoxaflor (5 ppb) or N. bombi exposure (50 000 spores) on larval mortality when tested in isolation but found an additive, negative effect when larvae received both stressors in combination. Individually, sulfoxaflor and N. bombi exposure each impaired larval growth, although the impact of combined exposure fell significantly short of the predicted sum of the individual effects (i.e. they interacted antagonistically). Ultimately, our results suggest that colony-level consequences of sulfoxaflor exposure for bumblebees may be mediated through direct effects on larvae. As sulfoxaflor is licensed for use globally, our findings highlight the need to understand how novel insecticides impact non-target insects at various stages of their development.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Nosema , Piridinas/toxicidade , Compostos de Enxofre/toxicidade , Animais
19.
Ecotoxicol Environ Saf ; 205: 111127, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32846293

RESUMO

Trichlorfon is an organophosphate insecticide that is widely used on fish farms to control parasitic infections. It has been detected in freshwater ecosystems as well as in fishery products. There is a growing body of evidence to suggest that certain feed additives may reduce or prevent pesticide-induced toxicity in fish. The aim of the present study was to determine whether acute exposure to trichlorfon would alter bioenergetic homeostasis and alter fatty acid profiles in muscles of silver catfish (Rhamdia quelen). We also sought to determine whether rutin prevents or reduces these effects. Cytosolic and mitochondrial creatine kinase (CK) and activities of complexes II-III and IV in muscle were significantly inhibited by exposure to 11 mg/L trichlorfon for 48 h compared to effects in the unexposed group. Total content of polyunsaturated fatty acids (omega-3 and omega-6) were significantly lower in muscle of silver catfish exposed to 11 mg/L trichlorfon for 48 h than in the unexposed group. Addition of 3 mg rutin/kg feed increased CK activity and prevented inhibition of complex IV activity, as well as preventing all alterations of muscle fatty acid profiles elicited by exposure to trichlorfon. No significant differences were observed between groups with respect to muscle adenylate kinase or pyruvate kinase activities, as well as total content of saturated and monounsaturated fatty acids. Our findings suggest that exposure (48 h) to 11 mg trichlorfon/L water inhibits cytosolic and mitochondrial CK activity in muscle. Trichlorfon also affects activities of complexes II-III and IV in respiratory chain, with important consequences for adenosine triphosphate production. The pesticide alters fatty acid profiles in the fish and endangers human consumers of the product. The most important finding of the present study is that inclusion of rutin improves bioenergetic homeostasis and muscle fatty acid profiles, suggesting that it reduces trichlorfon-induced muscle damage.


Assuntos
Peixes-Gato/metabolismo , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/metabolismo , Inseticidas/toxicidade , Músculos/efeitos dos fármacos , Rutina/farmacologia , Triclorfon/toxicidade , Trifosfato de Adenosina/metabolismo , Adenilato Quinase/metabolismo , Ração Animal , Animais , Peixes-Gato/crescimento & desenvolvimento , Creatina Quinase/metabolismo , Dieta , Aditivos Alimentares , Homeostase , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Músculos/metabolismo
20.
PLoS One ; 15(8): e0236694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745138

RESUMO

Methyl bromide (MB) is a fumigant that has been widely used for killing pests on plants in trade, soils, and structures worldwide due to its excellent permeability and insecticidal effect; however, MB should be replaced because it is an ozone-depleting substance. It is well-known that MB is highly toxic and hazardous to workers, but the effects of exposure in asymptomatic workers have not been explored. The purpose of this study is to investigate the impact of MB fumigation on the health of fumigators at a sensitive level. The electroencephalogram (EEG) and urinary bromide ion levels of 44 fumigators (the study group) and 20 inspectors (the control) were measured before and after fumigation work from February to August 2019 in Busan, Korea. The mean post-work concentration of bromide ion (18.311 µg/mg CRE) in the fumigators was significantly increased from the pre-work level (7.390 µg/mg CRE) (P<0.001). The fumigator post-work median frequencies (MDF) and alpha-to-theta ratios (ATR) of EEG index were significantly decreased compared to the pre-work values (P<0.05 for all indices). In contrast, there were no significant differences in inspector EEG indices and urinary bromide ion. The urinary bromide ion levels in all the subjects were negatively correlated with MDF (P = 0.032). In conclusion, fumigators' EEG indices and urinary bromide ion suggested that occupational exposure to MB negatively affected the health of workers, although the workers were asymptomatic.


Assuntos
Brometos/urina , Fumigação/efeitos adversos , Hidrocarbonetos Bromados/toxicidade , Inseticidas/toxicidade , Exposição Ocupacional/efeitos adversos , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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