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1.
Sci Rep ; 14(1): 15709, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977768

RESUMO

Honey bees are commonly co-exposed to pesticides during crop pollination, including the fungicide captan and neonicotinoid insecticide thiamethoxam. We assessed the impact of exposure to these two pesticides individually and in combination, at a range of field-realistic doses. In laboratory assays, mortality of larvae treated with captan was 80-90% greater than controls, dose-independent, and similar to mortality from the lowest dose of thiamethoxam. There was evidence of synergism (i.e., a non-additive response) from captan-thiamethoxam co-exposure at the highest dose of thiamethoxam, but not at lower doses. In the field, we exposed whole colonies to the lowest doses used in the laboratory. Exposure to captan and thiamethoxam individually and in combination resulted in minimal impacts on population growth or colony mortality, and there was no evidence of synergism or antagonism. These results suggest captan and thiamethoxam are each acutely toxic to immature honey bees, but whole colonies can potentially compensate for detrimental effects, at least at the low doses used in our field trial, or that methodological differences of the field experiment impacted results (e.g., dilution of treatments with natural pollen). If compensation occurred, further work is needed to assess how it occurred, potentially via increased queen egg laying, and whether short-term compensation leads to long-term costs. Further work is also needed for other crop pollinators that lack the social detoxification capabilities of honey bee colonies and may be less resilient to pesticides.


Assuntos
Captana , Sinergismo Farmacológico , Fungicidas Industriais , Inseticidas , Tiametoxam , Animais , Tiametoxam/toxicidade , Abelhas/efeitos dos fármacos , Abelhas/fisiologia , Inseticidas/toxicidade , Fungicidas Industriais/toxicidade , Captana/toxicidade , Larva/efeitos dos fármacos , Neonicotinoides/toxicidade , Tiazóis/toxicidade , Nitrocompostos/toxicidade
2.
Food Chem Toxicol ; 190: 114816, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38880465

RESUMO

Imidacloprid (IMI) is one of the top-notch insecticides that adversely affects the body organs including the liver. Malvidin (MAL) is a natural flavonoid which exhibits a wide range of pharmacological properties. This research was designed to evaluate the protective ability of MAL to counteract IMI instigated liver toxicity in rats. Thirty-two rats were divided into four groups including control, IMI (5mg/kg), IMI (5mg/kg) + MAL (10mg/kg) and MAL (10mg/kg) alone treated group. The recommended dosages were administrated through oral gavage for 4 weeks. It was revealed that IMI intoxication disrupted the PI3K/AKT and Nrf-2/Keap-1 pathway. Furthermore, the activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), heme-oxygenase-1 (OH-1) and glutathione reductase (GSR) were reduced while upregulating reactive oxygen species (ROS) and malondialdehyde (MDA) levels after IMI treatment. Moreover, IMI poisoning increased the levels of ALT (Alanine aminotransferase), AST (Aspartate transaminase), and ALP (Alkaline phosphatase) while reducing the levels of total proteins and albumin in hepatic tissues of rats. Besides, IMI administration escalated the expressions of Bcl-2-associated protein x (Bax) and cysteine-aspartic acid protease-3 (Caspase-3) while downregulating the expressions of B-cell lymphoma 2 (Bcl-2). Similarly, IMI intoxication, increased the levels of Interleukin-6 (IL-6), Nuclear factor kappa-B (NF-κB), Interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and the activity of cyclooxygenase-2 (COX-2). Furthermore, IMI disrupted the normal architecture of hepatic tissues. However, MAL treatment remarkably protected the liver tissues via regulating abovementioned disruptions.


Assuntos
Antocianinas , Doença Hepática Induzida por Substâncias e Drogas , Imidazóis , Proteína 1 Associada a ECH Semelhante a Kelch , Fígado , Fator 2 Relacionado a NF-E2 , NF-kappa B , Neonicotinoides , Nitrocompostos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Neonicotinoides/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Nitrocompostos/toxicidade , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , NF-kappa B/metabolismo , Ratos , Masculino , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Imidazóis/farmacologia , Antocianinas/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Transdução de Sinais/efeitos dos fármacos , Inseticidas/toxicidade , Ratos Wistar
3.
Ecotoxicol Environ Saf ; 281: 116582, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38905934

RESUMO

Molecular docking, pivotal in predicting small-molecule ligand binding modes, struggles with accurately identifying binding conformations and affinities. This is particularly true for neonicotinoids, insecticides whose impacts on ecosystems require precise molecular interaction modeling. This study scrutinizes the effectiveness of prominent docking software (Ledock, ADFR, Autodock Vina, CDOCKER) in simulating interactions of environmental chemicals, especially neonicotinoid-like molecules with nicotinic acetylcholine receptors (nAChRs) and acetylcholine binding proteins (AChBPs). We aimed to assess the accuracy and reliability of these tools in reproducing crystallographic data, focusing on semi-flexible and flexible docking approaches. Our analysis identified Ledock as the most accurate in semi-flexible docking, while Autodock Vina with Vinardo scoring function proved most reliable. However, no software consistently excelled in both accuracy and reliability. Additionally, our evaluation revealed that none of the tools could establish a clear correlation between docking scores and experimental dissociation constants (Kd) for neonicotinoid-like compounds. In contrast, a strong correlation was found with drug-like compounds, bringing to light a bias in considered software towards pharmaceuticals, thus limiting their applicability to environmental chemicals. The comparison between semi-flexible and flexible docking revealed that the increased computational complexity of the latter did not result in enhanced accuracy. In fact, the higher computational cost of flexible docking with its lack of enhanced predictive accuracy, rendered this approach useless for this class of compounds. Conclusively, our findings emphasize the need for continued development of docking methodologies, particularly for environmental chemicals. This study not only illuminates current software capabilities but also underscores the urgency for advancements in computational molecular docking as it is a relevant tool to environmental sciences.


Assuntos
Inseticidas , Simulação de Acoplamento Molecular , Neonicotinoides , Receptores Nicotínicos , Software , Receptores Nicotínicos/química , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/efeitos dos fármacos , Neonicotinoides/química , Neonicotinoides/toxicidade , Inseticidas/química , Inseticidas/toxicidade , Reprodutibilidade dos Testes , Proteínas de Transporte/química , Ligantes
4.
Anal Chim Acta ; 1314: 342796, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876515

RESUMO

BACKGROUND: Excessive pesticide residues in agricultural products could accumulate in organisms through the food chain, causing potential harm to human health. The investigation of dissipation kinetics and residues of pesticides in crops is crucial for the scientific application of pesticides and the mitigation of their adverse effects on human health. In vivo solid-phase microextraction (in vivo SPME) has unique advantages, but the research on field plants is still lacking and the quantitative correction methods need to be further developed. RESULTS: A method combining in vivo solid-phase microextraction with ultra-performance liquid chromatography-tandem mass spectrometry (in vivo SPME-UPLC-MS/MS) was developed to monitor the presence of acetamiprid, cyromazine, thiamethoxam and imidacloprid in cowpea fruits grown in the field. The sampling rates (Rs) were determined using both in vitro SPME in homogenized cowpea samples and in vivo SPME in intact cowpea fruit samples. The in vivo-Rs values were significantly higher than the in vitro-Rs for the same analyte, which were used for in vivo SPME correction. The accuracy of this method was confirmed by comparison with a QuEChERS-based approach and subsequently applied to trace pesticide residues in field-grown cowpea fruits. The residual concentrations of each pesticide positively correlated with application doses. After 7 days of application at two different doses, all of the pesticides had residual concentrations below China's maximum residue limits. Both experimental data and predictions indicated that a safe preharvest interval for these pesticides is 7 days; however, if the European Union standards are to be met, a safe preharvest interval for cyromazine should be at least 13 days. SIGNIFICANCE: This study highlights the advantages of in vivo SPME for simultaneous analysis and tracking of multiple pesticides in crops under field conditions. This technique is environmentally friendly, minimally invasive, highly sensitive, accurate, rapid, user-friendly, cost-effective, and capable of providing precise and timely data for long-term pesticide surveillance. Consequently, it furnishes valuable insights to guide the safe utilization of pesticides in agricultural production.


Assuntos
Neonicotinoides , Resíduos de Praguicidas , Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Triazinas , Vigna , Vigna/química , Espectrometria de Massas em Tandem/métodos , Neonicotinoides/análise , Microextração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Triazinas/análise , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Frutas/química
5.
Environ Sci Pollut Res Int ; 31(28): 41221-41245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38847950

RESUMO

In this work, the efficacy of two metal-organic frameworks (MIL-101(Fe) and NH2-MIL-101(Fe)) in eliminating acetamiprid (ATP) insecticide and eosin Y (EY) dye from aqueous solution is tested. An analysis was conducted on the developed nanocomposite's optical, morphological, and structural characteristics. The adsorption isotherm, kinetics, thermodynamics, reusability, and mechanisms for ATP and EY dye removal were assessed. NH2-MIL-101(Fe) adsorbed 76% and 90% of ATP pesticide and EY dye, respectively after 10 to 15 min in optimum conditions. For both adsorbents, with regard to explaining the isotherm data, the Langmuir model offered the most accurate description. Moreover, the adsorption of ATP and EY dye is described by the pseudo-second-order kinetic model. The maximum adsorption capacities of ATP and EY dye on MIL-101(Fe) were 57.6 and 48.9 mg/g compared to 70.5 and 97.8 mg/g using NH2-MIL-101(Fe). The greatest amount of ATP and EY dye clearance was obtained at a neutral medium for both adsorbents. The results of this investigation demonstrate the effectiveness of MIL-101(Fe) and NH2-MIL-101(Fe) as effective substances in the adsorption process for removing pesticides and dyes from aqueous solution.


Assuntos
Amarelo de Eosina-(YS) , Estruturas Metalorgânicas , Neonicotinoides , Poluentes Químicos da Água , Adsorção , Neonicotinoides/química , Estruturas Metalorgânicas/química , Cinética , Amarelo de Eosina-(YS)/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Termodinâmica
6.
Environ Int ; 189: 108811, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38870579

RESUMO

BACKGROUND: China produces and consumes a large amount of neonicotinoids. A non-negligible exposure to neonicotinoids might occur for Chinese pregnant women, but relevant data remain limited. OBJECTIVE: To investigate the exposure to neonicotinoids by urinary biomonitoring in pregnant women from Wenzhou City, East China. METHODS: We selected 432 pregnant women in Wenzhou City in 2022. A total of eight parent neonicotinoids and four metabolites were determined in single spot urine by liquid chromatography coupled to mass spectrometry. Basic characteristics, physical activity, pre-pregnant body mass index, and intake of drinking water and food were investigated by the questionnaire. Health risk was assessed by hazard quotient (HQ) and hazard index (HI) based on human safety thresholds derived from different health endpoints. RESULTS: Neonicotinoids and their metabolites in urine had a detection frequency between 0 % and 80.1 %. At least one neonicotinoid or metabolite was detected in 93.5 % of urine samples. Except for clothianidin (51.2 %) and N-desmethyl-acetamiprid (80.1 %), the detection frequencies of other neonicotinoids and metabolites ranged from 0 % to 43.8 %. The summed concentrations of all neonicotinoids and their metabolites ranged from < LOD to 222.83 µg/g creatinine with the median concentration of 2.58 µg/g creatinine. Maternal age, educational level, occupation, household income, screen time, and pre-pregnant body mass index were associated with detection frequencies or concentrations of neonicotinoids and their metabolites. Pregnant women with higher consumption frequencies of wheat, fresh vegetable, shellfish, fresh milk, and powdered milk had higher detection frequencies of neonicotinoids and their metabolites. Both HQ and HI were less than one. CONCLUSIONS: Overall, pregnant women in Wenzhou City showed a notable frequency of exposure to at least one neonicotinoid, although the exposure frequency for each specific neonicotinoid was generally low. Several food items derived from plants and animals were potential exposure sources. A low health risk was found based on current safety thresholds.


Assuntos
Monitoramento Biológico , Neonicotinoides , Humanos , Feminino , China , Gravidez , Neonicotinoides/urina , Neonicotinoides/análise , Adulto , Adulto Jovem , Inseticidas/urina , Inseticidas/análise , Exposição Ambiental/estatística & dados numéricos , Exposição Ambiental/análise , Cidades
7.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891887

RESUMO

With projections suggesting an increase in the global use of neonicotinoids, contemporary farmers can get caught on the "pesticide treadmill", thus creating ecosystem side effects. The aim of this study was to investigate the sorption/desorption behavior of acetamiprid, imidacloprid, and thiacloprid that controls their availability to other fate-determining processes and thus could be useful in leveling the risk these insecticides or their structural analogues pose to the environment, animals, and human health. Sorption/desorption isotherms in four soils with different organic matter (OC) content were modelled by nonlinear equilibrium models: Freundlich's, Langmuir's, and Temkin's. Sorption/desorption parameters obtained by Freundlich's model were correlated to soil physico-chemical characteristics. Even though the OC content had the dominant role in the sorption of the three insecticides, the role of its nature as well as the chemical structure of neonicotinoids cannot be discarded. Insecticides sorbed in the glassy OC phase will be poorly available unlike those in the rubbery regions. Imidacloprid will fill the sorption sites equally in the rubbery and glassy phases irrespective of its concentration. The sorption of thiacloprid at low concentrations and acetamiprid at high concentrations is controlled by hydrophilic aromatic structures, "trapping" the insecticides in the pores of the glassy phase of OC.


Assuntos
Inseticidas , Neonicotinoides , Nitrocompostos , Tiazinas , Neonicotinoides/química , Inseticidas/química , Nitrocompostos/química , Tiazinas/química , Adsorção , Solo/química , Poluentes do Solo/química , Piridinas/química , Imidazóis/química
8.
Sci Total Environ ; 942: 173685, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38825192

RESUMO

Pesticide mixtures are frequently utilized in agriculture, yet their cumulative effects on aquatic organisms remain poorly understood. Aquatic animals can be effective bioindicators and invasive bivalves, owing to their widespread distribution, provide an opportunity to assess these impacts. Glyphosate and imidacloprid, among the most prevalent pesticides globally, are frequently detected in freshwater systems in South America. This study aims to understand the cumulative effects of pesticide mixtures on aquatic organisms, using invasive Corbicula largillierti clams from a natural stream in northwestern Argentina. We conducted 48-hour exposure experiments using two concentrations of imidacloprid (20 and 200 µg L-1 a.i), two concentrations of glyphosate (0.3 and 3 mg L-1 a.i), and two combinations of these pesticides (both at low and high concentrations, respectively), simulating the direct contamination of both pesticides based on their agronomic recipe and observed values in Argentine aquatic environments. Clam metabolism was assessed through the examination of multiple oxidative stress parameters and measuring oxygen consumption rate as a proxy for standard metabolic rate (SMR). Our findings revealed that imidacloprid has a more pronounced effect compared to glyphosate. Imidacloprid significantly decreased clam SMR and cellular levels of reduced glutathione (GSH). However, when both pesticides were present, also cellular glycogen and thiobarbituric acid-reactive substances (TBARS) were affected. Proteins and glutathione S-Transferase (GST) activity were unaffected by either pesticide or their mixture at the assayed concentrations, highlighting the need to test several stress parameters to detect toxicological impacts. Our results indicated additive effects of imidacloprid and glyphosate across all measured parameters. The combination of multiple physiological and cytological biomarkers in invasive bivalves offers significant potential to enhance biomonitoring sensitivity and obtain insights into the origins and cellular mechanisms of chemical impacts. These studies can improve pollution regulatory policies and pesticide management.


Assuntos
Biomarcadores , Corbicula , Glicina , Glifosato , Neonicotinoides , Nitrocompostos , Poluentes Químicos da Água , Neonicotinoides/toxicidade , Animais , Nitrocompostos/toxicidade , Poluentes Químicos da Água/toxicidade , Glicina/análogos & derivados , Glicina/toxicidade , Biomarcadores/metabolismo , Argentina , Corbicula/efeitos dos fármacos , Herbicidas/toxicidade , Monitoramento Ambiental , Estresse Oxidativo/efeitos dos fármacos , Inseticidas/toxicidade
9.
Chemosphere ; 361: 142511, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825249

RESUMO

Environmental ambient temperature significantly impacts the metabolic activities of aquatic ectotherm organisms and influences the fate of various chemicals. Although numerous studies have shown that the acute lethal toxicity of most chemicals increases with increasing temperature, the impact of temperature on chronic effects - encompassing both lethal and sublethal endpoints - has received limited attention. Furthermore, the mechanisms linking temperature and toxicity, potentially unveiled by toxicokinetic-toxicodynamic models (TKTD), remains inadequately explored. This study investigated the effects of environmentally relevant concentrations of the insecticide imidacloprid (IMI) on the growth and survival of the freshwater amphipod Gammarus pulex at two different temperatures. Our experimental design was tailored to fit a TKTD model, specifically the Dynamic Energy Budget (DEB) model. We conducted experiments spanning three and six months, utilizing small G. pulex juveniles. We observed effects endpoints at least five times, employing both destructive and non-destructive methods, crucial for accurate model fittings. Our findings reveal that IMI at environmental concentrations (up to 0.3 µg/L) affects the growth and survival of G. pulex, albeit with limited effects, showing a 10% inhibition compared to the control group. These limited effects, observed in both lethal and sublethal aspects, suggest a different mode of action at low, environmentally-relevant concentrations in long-term exposure (3 months), in contrast to previous studies which applied higher concentrations and found that sublethal effects occurred at significantly lower levels than lethal effects in an acute test setting (4 days). Moreover, after parameterizing the DEB model for various temperatures, we identified a lower threshold for both lethal and sublethal effects at higher temperatures, indicating increased intrinsic sensitivity. Overall, this study contributes to future risk assessments considering temperature as a crucial factor and exemplifies the integration of the DEB model into experimental design for comprehensive toxicity evaluations.


Assuntos
Anfípodes , Inseticidas , Neonicotinoides , Nitrocompostos , Temperatura , Poluentes Químicos da Água , Neonicotinoides/toxicidade , Animais , Nitrocompostos/toxicidade , Anfípodes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Inseticidas/toxicidade , Toxicocinética , Imidazóis/toxicidade
10.
J Toxicol Sci ; 49(7): 301-311, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945841

RESUMO

Clothianidin (CLO), a neonicotinoid that is widely used in forests and agricultural areas, was recently reported to cause toxicity in mammals. Although sensitivity to chemicals varies between sexes and developmental stages, studies that comprehensively evaluate both males and females are limited. Therefore, in this study we utilized murine models to compare the sex-specific differences in behavioral effects following CLO exposure at different developmental stages. We orally administered CLO to male and female mice as a single high-dose solution (80 mg/kg) during the postnatal period (2-week-old), adolescence (6-week-old), or maturity (10-week-old), and subsequently evaluated higher brain function. The behavioral battery test consisted of open field, light/dark transition, and contextual/cued fear conditioning tests conducted at three and seven months of age. After the behavioral test, the brains were dissected and prepared for immunohistochemical staining. We observed behavioral abnormalities in anxiety, spatial memory, and cued memory only in female mice. Moreover, the immunohistochemical analysis showed a reduction in astrocytes within the hippocampus of female mice with behavioral abnormalities. The behavioral abnormalities observed in female CLO-treated mice were consistent with the typical behavioral abnormalities associated with hippocampal astrocyte dysfunction. It is therefore possible that the CLO-induced behavioral abnormalities are at least in part related to a reduction in astrocyte numbers. The results of this study highlight the differences in behavioral effects following CLO exposure between sexes and developmental stages.


Assuntos
Comportamento Animal , Guanidinas , Hipocampo , Neonicotinoides , Tiazóis , Animais , Feminino , Neonicotinoides/toxicidade , Guanidinas/toxicidade , Guanidinas/administração & dosagem , Masculino , Comportamento Animal/efeitos dos fármacos , Tiazóis/toxicidade , Tiazóis/administração & dosagem , Hipocampo/efeitos dos fármacos , Caracteres Sexuais , Medo/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Ansiedade/induzido quimicamente , Camundongos , Fatores Sexuais , Memória Espacial/efeitos dos fármacos , Administração Oral , Inseticidas/toxicidade
11.
Pestic Biochem Physiol ; 202: 105890, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879289

RESUMO

Cytochrome P450 plays a crucial role in regulating insect growth, development, and resisting a variety of stresses. Insect metamorphosis and response to external stress are altered by deleting CYP450 genes. In this study, we identified and analyzed a novel gene of CYP450 family, AccCYP6A13, from Apis cerana cerana, and explored its role in the response of Apis cerana cerana to adverse external stressors. It was found that the expression of AccCYP6A13 was spatiotemporal specificity. The expression level increased with age and reached its highest value in the adult stage. The primarily expressiong location were legs, brain, and epidermis of honeybees. Stress conditions can affect the expression of AccCYP6A13 depending on treatment times. RNA interference experiments have shown that knocking down AccCYP6A13 reduces antioxidant activity and deactivates detoxification enzymes, resulting in oxidative damage accumulation and a decline in detoxification capability in bees, as well as inhibiting numerous antioxidant genes. Additionally, knockdown of the AccCYP6A13 gene in Apis cerana cerana resulted in increased sensitivity to pesticides and increased mortality when treated with neonicotinoid pesticides such as thiamethoxam. AccCYP6A13 overexpression in a prokaryotic system further confirmed its role in resistance to oxidative stress. To summarize, AccCYP6A13 may play an essential role in the normal development and response to environmental stress in Apis cerana cerana. Furthermore, this study contributed to the theoretical understanding of bee resistance biology.


Assuntos
Sistema Enzimático do Citocromo P-450 , Proteínas de Insetos , Estresse Fisiológico , Animais , Abelhas/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Estresse Fisiológico/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inseticidas/toxicidade , Tiametoxam , Interferência de RNA , Neonicotinoides/toxicidade , Estresse Oxidativo
12.
Pestic Biochem Physiol ; 202: 105973, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879316

RESUMO

Using a high-efficiency insecticide in combination with fungicides that have different mechanisms of action is a conventional method in the current management of brown planthopper (BPH) resistance. In this study, we investigate the separate and combined effects of the low-toxicity fungicide validamycin and the non-cross-resistant insecticide imidacloprid on the fitness and symbiosis of BPH. These research results indicate that when the proportion of active ingredients in validamycin is combined with imidacloprid at a ratio of 1:30, the toxicity ratio and co-toxicity coefficient are 1.34 and 691.73, respectively, suggesting that the combination has a synergistic effect on the control of BPH. The number of yeast-like symbiotic (YLS) and dominant symbiotic (Noda) in the imidacloprid + validamycin groups were significantly lower than the other three treatment groups (validamycin, imidacloprid, and water). The results of the study on population fitness show that the lifespan of the BPH population in validamycin, imidacloprid, and imidacloprid + validamycin was shortened. Notably, the BPH populations in the imidacloprid + validamycin groups were significantly lower than other groups in terms of average generation cycle, intrinsic growth rate, net reproduction rate, finite rate of increase, and fitness. The Real-time quantitative PCR showed that validamycin and imidacloprid + validamycin can significantly inhibit the expression of the farnesyl diphosphate farnesyl transferase gene (EC2.5.1.21) and uricase gene (EC1.7.3.3), with imidacloprid + validamycin demonstrating the most pronounced inhibitory effect. Our research results can provide insights and approaches for delaying resistance and integrated management of BPH.


Assuntos
Hemípteros , Inseticidas , Neonicotinoides , Nitrocompostos , Simbiose , Animais , Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Inseticidas/farmacologia , Inositol/análogos & derivados , Inositol/farmacologia , Imidazóis/farmacologia , Fungicidas Industriais/farmacologia
13.
Pestic Biochem Physiol ; 202: 105939, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879330

RESUMO

The brown planthopper (BPH), Nilaparvata lugens is a devastating agricultural pest of rice, and they have developed resistance to many pesticides. In this study, we assessed the response of BPH nymphs to nitenpyram, imidacloprid, and etofenprox using contact and dietary bioassays, and investigated the underlying functional diversities of BPH glutathione-S-transferase (GST), carboxylesterase (CarE) and cytochrome P450 monooxygenase (P450) against these insecticides. Both contact and ingestion toxicity of nitenpyram to BPH were significantly higher than either imidacloprid or etofenprox. Under the LC50 concentration of each insecticide, they triggered a distinct response for GST, CarE, and P450 activities, and each insecticide induced at least one detoxification enzyme activity. These insecticides almost inhibited the expression of all tested GST, CarE, and P450 genes in contact bioassays but induced the transcriptional levels of these genes in dietary bioassays. Silencing of NlGSTD2 expression had the greatest effect on BPH sensitivity to nitenpyram in contact test and imidacloprid in dietary test. The sensitivities of BPH to insecticide increased the most in the contact test was etofenprox after silencing of NlCE, while the dietary test was nitenpyram. Knockdown of NlCYP408A1 resulted in BPH sensitivities to insecticide increasing the most in the contact test was nitenpyram, while the dietary test was imidacloprid. Taken together, these findings reveal that NlGSTD2, NlCE, and NlCYP408A1 play an indispensable role in the detoxification of the contact and ingestion toxicities of different types of insecticides to BPH, which is of great significance for the development of new strategies for the sucking pest control.


Assuntos
Carboxilesterase , Sistema Enzimático do Citocromo P-450 , Glutationa Transferase , Hemípteros , Inseticidas , Neonicotinoides , Nitrocompostos , Piretrinas , Interferência de RNA , Animais , Hemípteros/efeitos dos fármacos , Hemípteros/genética , Inseticidas/toxicidade , Inseticidas/farmacologia , Neonicotinoides/toxicidade , Neonicotinoides/farmacologia , Nitrocompostos/toxicidade , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Carboxilesterase/genética , Carboxilesterase/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Piretrinas/toxicidade , Piretrinas/farmacologia , Inativação Metabólica , Ninfa/efeitos dos fármacos , Ninfa/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Piridinas/toxicidade , Piridinas/farmacologia
14.
Pestic Biochem Physiol ; 202: 105935, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879327

RESUMO

Imidacloprid (IMI) is a contaminant widespread in surface water, causing serious intestinal damage in the common carp. Melatonin (MT), an endogenous indoleamine hormone, plays a crucial role in mitigating pesticide-induced toxicity. Our previous research has demonstrated that MT effectively reduces the production of intestinal microbial-derived signal peptidoglycan (PGN) induced by IMI, thereby alleviating intestinal tight junction injuries in the common carp. In this study, we performed a transcriptomic analysis to explore the effect of MT on the IMI exposure-induced gut damage of the common carp. The results elucidated that the ferroptosis, mitogen-activated protein kinases (MAPKs), and nucleotide oligomerization domain (NOD)-like signaling pathways were significantly associated with IMI exposure and MT treatment. Meanwhile, the exposure to IMI resulted in the formation of pyroptotic bodies and distinct morphological features of ferroptosis, both mitigated with the addition of MT. Immunofluorescence double staining demonstrated that MT abolished the elevated expression of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and Gasdermin D (GSDMD) induced by IMI, as well as reduced expression of ferritin heavy chains (FTH) and glutathione peroxidase 4 (GPX4) in gut tissues. Subsequently, we found that the exposure to IMI or PGN enhanced the expression of toll-like receptors (TLR) 2 (a direct recognition receptor of PGN) triggering the P38MAPK signaling pathway, thereby aggravating the process of pyroptosis and ferroptosis of cell models. The addition of MT or SB203580 (a P38MAPK inhibitor) significantly reduced pyroptotic cells, and also decreased iron accumulation. Consequently, these results indicate that MT alleviates IMI-induced pyroptosis and ferroptosis in the gut of the common carp through the PGN/TLR2/P38MAPK pathway.


Assuntos
Carpas , Ferroptose , Melatonina , Neonicotinoides , Nitrocompostos , Peptidoglicano , Piroptose , Animais , Carpas/metabolismo , Ferroptose/efeitos dos fármacos , Melatonina/farmacologia , Piroptose/efeitos dos fármacos , Neonicotinoides/farmacologia , Neonicotinoides/toxicidade , Peptidoglicano/farmacologia , Nitrocompostos/toxicidade , Nitrocompostos/farmacologia , Inseticidas/toxicidade , Intestinos/efeitos dos fármacos
15.
Anal Methods ; 16(26): 4301-4309, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38887921

RESUMO

This study presents a novel colorimetric aptasensor, which seamlessly integrates gold nanoparticles (AuNPs) with the amplification potential of the hybridization chain reaction (HCR) for enhanced detection of acetamiprid. The aptamer, hybridized with a partially complementary strand that is covalently linked to AuNPs, serves as the recognition element for acetamiprid. The free end sequence of the aptamer, distal from the AuNP surface, functions as the initiating strand for the HCR, triggering the amplification process. In the absence of acetamiprid, the HCR efficiently occurs, conferring robust salt tolerance to the AuNPs and maintaining their characteristic red coloration. However, in the presence of acetamiprid, the aptamer preferentially binds to its target, disrupting the double-stranded structure and leading to the dissociation of the aptamer from the AuNPs. This dissociation results in a decrease in the HCR product, subsequently diminishing the salt tolerance of AuNPs and triggering a colorimetric transition from red to gray. This integration enhances sensitivity to 3.14 nM. Additionally, carbon quantum dots (CQDs) transduce colorimetric signals to fluorescent ones, further boosting the sensitivity to 0.24 nM. The aptasensor exhibits excellent selectivity and robustness. Real-world testing on tomato, peach, and lettuce shows recoveries of 98.50% to 100.36% with low standard deviations, validating its utility for pesticide residue analysis and food safety. This study provides a powerful tool for rapid and accurate pesticide detection, crucial for food safety.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Colorimetria , Ouro , Nanopartículas Metálicas , Neonicotinoides , Hibridização de Ácido Nucleico , Ouro/química , Neonicotinoides/análise , Neonicotinoides/química , Nanopartículas Metálicas/química , Colorimetria/métodos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Pontos Quânticos/química , Contaminação de Alimentos/análise , Inseticidas/análise , Inseticidas/química
16.
Vet Med Sci ; 10(4): e1500, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38864312

RESUMO

BACKGROUND: Sarcoptic mange is rare in cats. The main symptoms reported in cases of feline sarcoptic mange include crusty lesions and pruritus, although these may vary in severity among individuals. OBJECTIVES: This report describes three cats infested with Sarcoptes scabiei, all presenting with pruritus and excoriation. METHODS: The diagnosis was confirmed by microscopic observation of skin scrape samples. RESULTS: All three cats were treated successfully using moxidectin and imidacloprid, selamectin and ivermectin, respectively. CONCLUSIONS: The clinical presentation of feline scabies appears to be more variable in cats than in dogs. Infestation with S. scabiei should be considered a differential diagnosis for cats presenting with pruritic inflammatory skin disease.


Assuntos
Doenças do Gato , Sarcoptes scabiei , Escabiose , Animais , Escabiose/veterinária , Escabiose/tratamento farmacológico , Escabiose/diagnóstico , Doenças do Gato/parasitologia , Doenças do Gato/tratamento farmacológico , Doenças do Gato/diagnóstico , Gatos , Masculino , Feminino , Polônia , Sarcoptes scabiei/efeitos dos fármacos , Ivermectina/uso terapêutico , Ivermectina/análogos & derivados , Nitrocompostos/uso terapêutico , Neonicotinoides/uso terapêutico , Inseticidas/uso terapêutico , Macrolídeos
17.
Proc Biol Sci ; 291(2024): 20232811, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38864325

RESUMO

Pesticides have been identified as major drivers of insect biodiversity loss. Thus, the study of their effects on non-pest insect species has attracted a lot of attention in recent decades. In general toxicology, the 'gold standard' to assess the toxicity of a substance is to measure mass-specific LD50 (i.e. median lethal dose per unit body mass). In entomology, reviews attempting to compare these data across all available studies are lacking. To fill this gap in knowledge, we performed a systematic review of the lethality of imidacloprid for adult insects. Imidacloprid is possibly the most extensively studied insecticide in recent times, yet we found that little is comparable across studies, owing to both methodological divergence and missing estimates of body mass. By accounting for body mass whenever possible, we show how imidacloprid sensitivity spans across an apparent range of approximately six orders of magnitude across insect species. Very high variability within species can also be observed owing to differences in exposure methods and observation time. We suggest that a more comparable and comprehensive approach has both biological and economic relevance. Ultimately, this would help to identify differences that could direct research towards preventing non-target species from being negatively affected.


Assuntos
Imidazóis , Insetos , Inseticidas , Neonicotinoides , Nitrocompostos , Especificidade da Espécie , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Animais , Inseticidas/toxicidade , Insetos/efeitos dos fármacos , Imidazóis/toxicidade , Dose Letal Mediana
18.
BMC Vet Res ; 20(1): 256, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867202

RESUMO

Acetamiprid (ACDP) is a widely used neonicotinoid insecticide that is popular for its efficacy in controlling fleas in domestic settings and for pets. Our study aims to offer a comprehensive examination of the toxicological impacts of ACDP and the prophylactic effects of cinnamon nanoemulsions (CMNEs) on the pathological, immunohistochemical, and hematological analyses induced by taking ACDP twice a week for 28 days. Forty healthy rats were divided into four groups (n = 10) at random; the first group served as control rats; the second received CMNEs (2 mg/Kg body weight); the third group received acetamiprid (ACDP group; 21.7 mg/Kg body weight), and the fourth group was given both ACDP and CMNEs by oral gavage. Following the study period, tissue and blood samples were extracted and prepared for analysis. According to a GC-MS analysis, CMNEs had several bioactive ingredients that protected the liver from oxidative stress by upregulating antioxidant and anti-inflammatory agents. Our findings demonstrated that whereas ACDP treatment considerably boosted white blood cells (WBCs) and lymphocytes, it significantly lowered body weight gain (BWG), red blood cells (RBCs), hemoglobin (Hb), hematocrit (HCT), and platelets (PLT). ACDP notably reduced antioxidant enzyme activities: superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) and elevated hydrogen peroxide and malondialdehyde levels compared with other groups. ACDP remarkably raised alanine aminotransferase (ALT), aspartate amino transaminase (AST), and alkaline phosphatase (ALP) levels.Moreover, the histopathological and immunohistochemistry assays discovered a severe toxic effect on the liver and kidney following ACDP delivery. Furthermore, cyclooxygenase 2 (COX-2) + immunoexpression was enhanced after treatment with CMNEs. All of the parameters above were returned to nearly normal levels by the coadministration of CMNEs. The molecular docking of cinnamaldehyde with COX-2 also confirmed the protective potential of CMNEs against ACDP toxicity. Our findings highlighted that the coadministration of CMNEs along with ACDP diminished its toxicity by cutting down oxidative stress and enhancing antioxidant capacity, demonstrating the effectiveness of CMNEs in lessening ACDP toxicity.


Assuntos
Cinnamomum zeylanicum , Emulsões , Inseticidas , Fígado , Simulação de Acoplamento Molecular , Neonicotinoides , Animais , Neonicotinoides/farmacologia , Cinnamomum zeylanicum/química , Inseticidas/toxicidade , Ratos , Emulsões/química , Emulsões/farmacologia , Masculino , Fígado/efeitos dos fármacos , Fígado/patologia , Rim/efeitos dos fármacos , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Antioxidantes/farmacologia , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Nefropatias/patologia , Ratos Sprague-Dawley
19.
J Agric Food Chem ; 72(25): 14141-14151, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864686

RESUMO

The cotton aphid, Aphis gossypii, is a polyphagous pest that stunts host plant growth via direct feeding or transmitting plant virus. Due to the long-term application of insecticides, A. gossypii has developed different levels of resistance to numerous insecticides. We found that five field populations had evolved multiple resistances to neonicotinoids. To explore the resistance mechanism mediated by uridine diphosphate glycosyltransferases (UGTs), two upregulated UGT genes in these five strains, UGT350C3 and UGT344L7, were selected for functional analysis of their roles in neonicotinoid detoxification. Transgenic Drosophila bioassay results indicated that compared with the control lines, the UGT350C3 and UGT344L7 overexpression lines were more tolerant to thiamethoxam, imidacloprid, and dinotefuran. Knockdown of UGT350C3 and UGT344L7 significantly increased A. gossypii sensitivity to thiamethoxam, imidacloprid, and dinotefuran. Molecular docking analysis demonstrated that these neonicotinoids could bind to the active pockets of UGT350C3 and UGT344L7. This study provides functional evidence of neonicotinoid detoxification mediated by UGTs and will facilitate further work to identify strategies for preventing the development of neonicotinoid resistance in insects.


Assuntos
Afídeos , Glicosiltransferases , Resistência a Inseticidas , Inseticidas , Neonicotinoides , Nitrocompostos , Animais , Afídeos/genética , Afídeos/enzimologia , Afídeos/efeitos dos fármacos , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Neonicotinoides/química , Inseticidas/farmacologia , Inseticidas/química , Inseticidas/metabolismo , Resistência a Inseticidas/genética , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Glicosiltransferases/química , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Tiametoxam , Drosophila/genética , Drosophila/enzimologia , Drosophila/efeitos dos fármacos , Drosophila/metabolismo , Guanidinas
20.
J Hazard Mater ; 474: 134787, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38823101

RESUMO

The developmental toxicity effects of neonicotinoid pesticides such as clothianidin have not been fully explored in agricultural applications. This is particularly noteworthy because such pesticides significantly impact the survival rates of invertebrates, with arthropod larvae being particularly vulnerable. This study aimed to address this research gap by specifically investigating the toxicological effects of clothianidin on the developmental stages of the larvae of the economically important aquaculture species Penaeus vannamei. In these experiments, shrimp eggs were exposed to seawater containing different concentrations of clothianidin beginning at N1, and each phase was observed and analyzed to determine its toxic impact on larval development. These results revealed that clothianidin induces an increase in deformity rates and triggers abnormal cell apoptosis. It also significantly reduced survival rates and markedly decreased body length and heart rate in the later stages of larval development (P3). Transcriptomic analysis revealed disruptions in larval DNA integrity, protein synthesis, and signal transduction caused by clothianidin. To survive prolonged exposure, larvae may attempt to maintain their viability by repairing cell structures and enhancing signal transduction mechanisms. This study offers the first empirical evidence of the toxicity of clothianidin to arthropod larvae, underscoring the impact of environmental pollution on aquatic health.


Assuntos
Guanidinas , Inseticidas , Larva , Neonicotinoides , Penaeidae , Tiazóis , Animais , Larva/efeitos dos fármacos , Neonicotinoides/toxicidade , Guanidinas/toxicidade , Tiazóis/toxicidade , Inseticidas/toxicidade , Penaeidae/efeitos dos fármacos , Penaeidae/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Apoptose/efeitos dos fármacos
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