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1.
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
2.
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
3.
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
4.
Pestic Biochem Physiol ; 202: 105958, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879340

RESUMO

The wheat aphid Sitobion miscanthi is a dominant and destructive pest in agricultural production. Insecticides are the main substances used for effective control of wheat aphids. However, their extensive application has caused severe resistance of wheat aphids to some insecticides; therefore, exploring resistance mechanisms is essential for wheat aphid management. In the present study, CYP6CY2, a new P450 gene, was isolated and overexpressed in the imidacloprid-resistant strain (SM-R) compared to the imidacloprid-susceptible strain (SM-S). The increased sensitivity of S. miscanthi to imidacloprid after knockdown of CYP6CY2 indicates that it could be associated with imidacloprid resistance. Subsequently, the posttranscriptional regulation of CYP6CY2 in the 3' UTR by miR-3037 was confirmed, and CYP6CY2 participated in imidacloprid resistance. This finding is critical for determining the role of P450 in relation to the resistance of S. miscanthi to imidacloprid. It is of great significance to understand this regulatory mechanism of P450 expression in the resistance of S. miscanthi to neonicotinoids.


Assuntos
Afídeos , Sistema Enzimático do Citocromo P-450 , Resistência a Inseticidas , Inseticidas , MicroRNAs , Neonicotinoides , Nitrocompostos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Animais , Inseticidas/farmacologia , Resistência a Inseticidas/genética , Afídeos/genética , Afídeos/efeitos dos fármacos , MicroRNAs/genética , MicroRNAs/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Imidazóis/farmacologia
5.
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
6.
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
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.
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
9.
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
10.
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
11.
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
12.
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
13.
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
14.
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
15.
PLoS One ; 19(6): e0290858, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38833488

RESUMO

The tarnished plant bug, (TPB) Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) is a key pest of cotton in the midsouth region and some areas of the eastern United States. Its control methods have been solely based on chemical insecticides which has contributed to insecticidal resistance and shortened residual periods for control of this insect pest. This study was conducted over a two-year period and examined the efficacy and residual effect of four commercial insecticides including lambda-cyhalothrin (pyrethroid), acephate (organophosphate), imidacloprid (neonicotinoid), and sulfoxaflor (sulfoxamine). The effectiveness and residual effects of these insecticides were determined by application on cotton field plots on four different dates during each season using three different concentrations (high: highest labeled commercial dose (CD), medium: 1/10 of the CD, low: 1/100 of the CD) on field cotton plots. Four groups of cotton leaves were randomly pulled from each treated plot and control 0-, 2-, 4-, 7-, and 9-days post treatment (DPT) and exposed to a lab colony of TPB adults. One extra leaf sample/ plot/ spray /DPT interval (0-2-4-7-9-11) during 2016 was randomly collected from the high concentration plots and sent to Mississippi State Chemical Laboratory for residual analysis. Mortality of TPB adults was greatest for those placed on leaves sprayed with the organophosphate insecticide with mortalities (%) of 81.7±23.4 and 63.3±28.8 (SE) 1-day after exposure (DAE) on leaves 0-DPT with the high concentration for 2016 and 2017, respectively, reaching 94.5±9.5 and 95.4±7.6 6-DAE each year. Mortality to all insecticides continued until 9 and 4-DPT for high and medium concentrations, respectively. However, organophosphate (39.4±28.6) and pyrethroid (24.4±9.9) exhibited higher mortality than sulfoxamine (10.6±6.6) and the neonicotinoid (4.0±1.5) 7-DAE on 9-DPT leaves with the high concentration. Based on our results using the current assay procedure, TPB adults were significantly more susceptible to contact than systemic insecticides and due to its residual effect, organophosphate could kill over 80% of the TPB population 7-DPT.


Assuntos
Gossypium , Inseticidas , Neonicotinoides , Nitrilas , Nitrocompostos , Fosforamidas , Piretrinas , Inseticidas/farmacologia , Gossypium/parasitologia , Animais , Piretrinas/farmacologia , Neonicotinoides/farmacologia , Mississippi , Nitrilas/farmacologia , Nitrocompostos/farmacologia , Controle de Insetos/métodos , Heterópteros/efeitos dos fármacos , Imidazóis/farmacologia , Hemípteros/efeitos dos fármacos , Compostos Organotiofosforados , Piridinas , Compostos de Enxofre
16.
Sci Rep ; 14(1): 13047, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844538

RESUMO

Neonicotinoids, a relatively new widely used class of insecticide is used in agriculture to control insect populations. We examined the capacity of ancestral exposure to the neonicotinoid thiacloprid (thia) to induce transgenerational effects on thyroid tissue. Pregnant outbred Swiss female mice were exposed to thia at embryonic days E6.5 to E15.5 using 0, 0.6, and 6 mg/kg/day doses. Thyroid paraffin sections were prepared for morphology analysis. We apply ELISA method to measure T4 and TSH levels, RT-qPCR for gene expression analysis, ChIP-qPCR techniques for sperm histone H3K4me3 analysis, and immunofluorescence microscopy and western blots for protein detection. We observed an alteration in the morphology of thyroids in both males and females in the F3 generation. We observed an increase in T4 hormone in F1 females and a significant T4 level decrease in F3 males. T4 changes in F1 females were associated with a TSH increase. We found that the amount of Iodothyronine Deiodinase 1 (DIO1) (an enzyme converting T4 to T3) was decreased in both F1 and F3 generations in female thyroids. GNAS protein which is important for thyroid function has increased in female thyroids. Gene expression analysis showed that the expression of genes encoding thyroid gland development, chromatin, biosynthesis and transport factors were affected in the thyroid gland in both sexes in F1 and F3. The analysis of sperm histone H3K4me3 showed that H3K4me3 occupancy at the Dio1 locus has decreased while Thyroglobulin (Tg) and Matrix Metallopeptidase 2 (Mmp2) genes have increased H3K4me3 occupancy in the sperm of F3 mice. Besides, DNA methylation analysis of our previously published datasets showed that, in the sperm of F1 and F3 thia-derived mice, several genes related to thyroid function show consistent alterations. Our data suggest that ancestral exposure to thiacloprid affects thyroid function not only in exposed but also in indirectly exposed F3 generation.


Assuntos
Neonicotinoides , Glândula Tireoide , Animais , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Feminino , Neonicotinoides/toxicidade , Camundongos , Masculino , Tiazinas/toxicidade , Gravidez , Histonas/metabolismo , Tiroxina/metabolismo , Iodeto Peroxidase/metabolismo , Iodeto Peroxidase/genética , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Inseticidas/toxicidade , Tireotropina/sangue , Tireotropina/metabolismo , Fatores Sexuais
17.
J Agric Food Chem ; 72(23): 12967-12974, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814790

RESUMO

Structure-activity relationships of diazinoyl nicotinic insecticides (diazinoyl isomers and 5- or 6-substituted pyrazin-2-oyl analogues) are considered in terms of affinity to the insect nicotinic acetylcholine receptor (nAChR) and insecticidal activity against the imidacloprid-resistant brown planthopper. Among the test compounds, 3-(6-chloropyridin-3-ylmethyl)-2-(pyrazinoyl)iminothiazoline shows the highest potency in nAChR affinity and insecticidal activity. Aplysia californica acetylcholine binding protein (AChBP) mutants (Y55W + Q57R and Y55W + Q57T) are utilized to compare molecular recognition of nicotinic insecticides with diverse pharmacophores. N-nitro- or N-cyanoimine imidacloprid or acetamiprid, respectively, exhibits a high affinity to these AChBP mutants at a similar potency level. Intriguingly, the pyrazin-2-oyl analogue has a higher affinity to AChBP Y55W + Q57R than that to Y55W + Q57T, thereby indicating that pyrazine nitrogen atoms contact Arg57 guanidinium and Trp55 indole NH. Furthermore, nicotine prefers AChBP Y55W + Q57T over Y55W + Q57R, conceivably suggesting that the protonated nicotine is repulsed by Arg57 guanidinium, consistent with its inferior potency to insect nAChR.


Assuntos
Hemípteros , Proteínas de Insetos , Inseticidas , Neonicotinoides , Receptores Nicotínicos , Animais , Inseticidas/química , Inseticidas/farmacologia , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Hemípteros/química , Hemípteros/genética , Hemípteros/efeitos dos fármacos , Hemípteros/metabolismo , Relação Estrutura-Atividade , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Neonicotinoides/química , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Nitrocompostos/química , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Aplysia/química , Aplysia/metabolismo , Aplysia/genética , Nicotina/química , Nicotina/metabolismo , Nicotina/análogos & derivados , Nicotina/farmacologia
18.
J Agric Food Chem ; 72(23): 12956-12966, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38820064

RESUMO

Bees, one of the most vital pollinators in the ecosystem and agriculture, are currently threatened by neonicotinoids. To explore the molecular mechanisms of neonicotinoid toxicity to bees, the different binding modes of imidacloprid, thiacloprid, and flupyradifurone with nicotinic acetylcholine receptor (nAChR) α1ß1 and cytochrome P450 9Q3 (CYP9Q3) were studied using homology modeling and molecular dynamics simulations. These mechanisms provided a basis for the design of compounds with a potential low bee toxicity. Consequently, we designed and synthesized a series of triazinone derivatives and assessed their bioassays. Among them, compound 5a not only displayed substantially insecticidal activities against Aphis glycines (LC50 = 4.40 mg/L) and Myzus persicae (LC50 = 6.44 mg/L) but also had low toxicity to Apis mellifera. Two-electrode voltage clamp recordings further confirmed that compound 5a interacted with the M. persicae nAChR α1 subunit but not with the A. mellifera nAChR α1 subunit. This work provides a paradigm for applying molecular toxic mechanisms to the design of compounds with low bee toxicity, thereby aiding the future rational design of eco-friendly nicotinic insecticides.


Assuntos
Proteínas de Insetos , Inseticidas , Neonicotinoides , Receptores Nicotínicos , Abelhas/efeitos dos fármacos , Animais , Inseticidas/química , Inseticidas/toxicidade , Neonicotinoides/química , Neonicotinoides/toxicidade , Neonicotinoides/metabolismo , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/química , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Afídeos/efeitos dos fármacos , Nitrocompostos/química , Nitrocompostos/toxicidade , Desenho de Fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/química , Simulação de Dinâmica Molecular , Ligação Proteica , Tiazinas
19.
Sci Total Environ ; 941: 173257, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38761944

RESUMO

The combined exposure of heavy metals and organic contaminates can influence the transport and accumulation of heavy metals within the soil-rice system. However, the underlying mechanisms of this process remain largely unknown. Herein, this study investigated the influence of three neonicotinoid insecticides (NIs), including imidacloprid (IMI), clothianidin (CLO), and thiamethoxam (THI), on the Cd transport and accumulation in rice (Oryza sativa) at different growth stages. Particular focus lied on their complex interaction and key genes expression involved in Cd transport. Results showed that the interaction between Cd and NIs was the dominant factor affecting Cd transport and accumulation in rice exposed to NIs. All three NIs chelated with Cd with nitrogen (N) on the IMI and THI nitro groups, and the N on the CLO nitro guanidine group. Interestingly, this chelation behavior varied between the tillering stage and the filling/ripening stages, resulting in diverse patterns of Cd accumulation in rice tissues. During the tillering stage, all three NIs considerably inhibited Cd bioavailability and transport to the above-ground part, lowering Cd content in the stem and leaf. The inhibition was increased with stronger chelation ability in the order of IMI (-0.46 eV) > CLO (-0.41 eV) > THI (-0.11 eV), with IMI exhibiting the highest binding energy for Cd and reducing Cd transfers from root to stem by an impressive 94.49 % during the tillering stage. Conversely, during the filling/ripening stages, NIs facilitated Cd accumulation in rice roots, stems, leaves, and grains. This was mainly attributed to the generation of nitrate ions and the release of Cd2+ during the chelation between Cd and NIs under drainage condition. These findings provide theoretical basis for the treatment of combined contamination in field and deep insights into understanding the interaction of organic contaminants with heavy metals in rice culture process.


Assuntos
Cádmio , Inseticidas , Neonicotinoides , Oryza , Poluentes do Solo , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Cádmio/metabolismo , Neonicotinoides/metabolismo , Inseticidas/metabolismo , Poluentes do Solo/metabolismo , Guanidinas/metabolismo , Quelantes , Nitrocompostos/metabolismo , Tiazóis/metabolismo
20.
Environ Sci Pollut Res Int ; 31(26): 37923-37942, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38769264

RESUMO

Neonicotinoids, as the fastest-growing class of insecticides, currently account for over 25% of the global pesticide market. Their effectiveness in controlling a wide range of pests that pose a threat to croplands, home yards/gardens, and golf course greens cannot be denied. However, the extensive use of neonicotinoids has resulted in significant declines in nontarget organisms such as pollinators, insects, and birds. Furthermore, the potential chronic, sublethal effects of these compounds on human health remain largely unknown. To address these pressing issues, it is crucial to explore and understand the capabilities of electrochemical sensors in detecting neonicotinoid residues. Surprisingly, despite the increasing importance of this topic, no comprehensive review article currently exists in the literature. Therefore, our proposed review aims to bridge this gap by providing a thorough analysis of the use of electrochemical methods for neonicotinoid determination. In this review article, we will delve into various aspects of electrochemical analysis, including the influence of electrode materials, employed techniques, and the different types of electrode mechanisms utilized. By synthesizing and analysing the existing research in this field, our review will offer valuable insights and guidance to researchers, scientists, and policymakers alike.


Assuntos
Inseticidas , Neonicotinoides , Neonicotinoides/análise , Inseticidas/análise , Técnicas Eletroquímicas , Monitoramento Ambiental/métodos , Animais
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