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1.
J Environ Sci (China) ; 147: 322-331, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003050

RESUMO

To investigate the associations between isocarbophos and isofenphos with impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2DM), and to assess the mediation roles of inflammation cells. There were 2701 participants in the case-control study, including 896 patients with T2DM, 900 patients with IFG, 905 subjects with NGT. Plasma isocarbophos and isofenphos concentrations were measured using gas chromatography and triple quadrupole tandem mass spectrometry. Generalized linear models were used to calculate the relationships between plasma isofenphos and isocarbophos levels with inflammatory factor levels and T2DM. Inflammatory cell was used as mediators to estimate the mediating effects on the above associations. Isocarbophos and isofenphos were positively related with T2DM after adjusting for other factors. The odds ratio (95% confidence interval) (OR (95%CI)) for T2DM was 1.041 (1.015, 1.068) and for IFG was 1.066 (1.009, 1.127) per unit rise in ln-isocarbophos. The prevalence of T2DM increased by 6.4% for every 1 unit more of ln-isofenphos (OR (95% CI): 1.064 (1.041, 1.087)). Additionally, a 100% rise in ln-isocarbophos was linked to 3.3% higher ln-HOMA2IR and a 0.029 mmol/L higher glycosylated hemoglobin (HbA1c) (95% CI: 0.007, 0.051). While a 100% rise in ln-isofenphos was linked to increase in ln-HOMA2 and ln-HOMA2IR of 5.8% and 3.4%, respectively. Furthermore, white blood cell (WBC) and neutrophilic (NE) were found to be mediators in the relationship between isocarbophos and T2DM, and the corresponding proportions were 17.12% and 17.67%, respectively. Isofenphos and isocarbophos are associated with IFG and T2DM in the rural Chinese population, WBC and NE have a significant role in this relationship.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Estudos de Casos e Controles , Inseticidas , Glicemia/análise , Malation/análogos & derivados , Compostos Organotiofosforados , China , Adulto , Inflamação
2.
Proc Natl Acad Sci U S A ; 121(28): e2402407121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38959045

RESUMO

Trade-offs between evolutionary gain and loss are prevalent in nature, yet their genetic basis is not well resolved. The evolution of insect resistance to insecticide is often associated with strong fitness costs; however, how the fitness trade-offs operates remains poorly understood. Here, we show that the mitogen-activated protein kinase (MAPK) pathway and its upstream and downstream actors underlie the fitness trade-offs associated with insecticide resistance in the whitefly Bemisia tabaci. Specifically, we find a key cytochrome P450 gene CYP6CM1, that confers neonicotinoids resistance to in B. tabaci, is regulated by the MAPKs p38 and ERK through their activation of the transcription factor cAMP-response element binding protein. However, phosphorylation of p38 and ERK also leads to the activation of the transcription repressor Cap "n" collar isoform C (CncC) that negatively regulates exuperantia (Ex), vasa (Va), and benign gonial cell neoplasm (Bg), key genes involved in oogenesis, leading to abnormal ovary growth and a reduction in female fecundity. We further demonstrate that the transmembrane G protein-coupled receptor (GPCR) neuropeptide FF receptor 2 (NPFF2) triggers the p38 and ERK pathways via phosphorylation. Additionally, a positive feedback loop between p38 and NPFF2 leads to the continuous activation of the MAPK pathways, thereby constitutively promoting neonicotinoids resistance but with a significant reproductive cost. Collectively, these findings provide fundamental insights into the role of cis-trans regulatory networks incurred by GPCR-MAPK signaling pathways in evolutionary trade-offs and applied knowledge that can inform the development of strategies for the sustainable pest control.


Assuntos
Hemípteros , Proteínas de Insetos , Resistência a Inseticidas , Sistema de Sinalização das MAP Quinases , Receptores Acoplados a Proteínas G , Animais , Hemípteros/genética , Hemípteros/metabolismo , Resistência a Inseticidas/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Feminino , Inseticidas/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética
3.
Sci Rep ; 14(1): 16325, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009775

RESUMO

Mosquitoes are important vectors for the transmission of several infectious diseases that lead to huge morbidity and mortality. The exhaustive use of synthetic insecticides has led to widespread resistance and environmental pollution. Using essential oils and nano-emulsions as novel insecticides is a promising alternative approach for controlling vector borne diseases. In the current study, Lantana camara EO and NE were evaluated for their larvicidal and pupicidal activities against Anopheles culicifacies. The inhibitory effect of EO and NE on AChE, NSE (α/ß), and GST was also evaluated and compared. GC-MS analysis of oil displayed 61 major peaks. The stable nano-emulsion with an observed hydrodynamic diameter of 147.62 nm was formed using the o/w method. The nano-emulsion exhibited good larvicidal (LC50 50.35 ppm and LC90 222.84 ppm) and pupicidal (LC50 54.82 ppm and LC90 174.58 ppm) activities. Biochemical evaluations revealed that LCEO and LCNE inhibited AChE, NSE (α/ß), and GST, displaying LCNE to be a potent binder to AChE and NSE enzyme, whereas LCEO showed higher binding potency towards GST. The nano-emulsion provides us with novel opportunities to target different mosquito enzymes with improved insecticidal efficacy. Due to its natural origin, it can be further developed as a safer and more potent larvicide/insecticide capable of combating emerging insecticide resistance.


Assuntos
Anopheles , Emulsões , Inseticidas , Lantana , Larva , Óleos Voláteis , Anopheles/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Animais , Lantana/química , Inseticidas/farmacologia , Inseticidas/química , Larva/efeitos dos fármacos , Cinética , Acetilcolinesterase/metabolismo , Glutationa Transferase/metabolismo , Glutationa Transferase/antagonistas & inibidores , Mosquitos Vetores/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Controle de Mosquitos/métodos
4.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 568-576, jul. 2024. ilus
Artigo em Espanhol | LILACS | ID: biblio-1538065

RESUMO

This study aimed to determine the repellent and insecticidal activity of four essential oils (EOs) from plants collected in the Chocó rain forest, Colombia, against T. castaneum . Conventional hydrodistillation was used to obtain the EOs. The repellent and insecticidal activities were evaluated by the preference area and gas dispersion methods, espectively. Statistical differences (p<0.05) were determined by applying a student's t-test. EOs of Siparuna guianensis, S. conica, Piper marginatum, and Nectandra acutifolia showed excellent repellent properties as the main findings, highlighting S. conicaEO with 84% repellency (1-hµL/cm2), while P. marginatum showed to be bioactive to the dose of 500 µL/mL (72 h), inducing mortality of 100% of the exposed population. In conclusion, the results evidenced the repellent properties of the EOs evaluated against T. castaneum , which allows us to conclude that these plant species are potential natural sources producing bio-repellents that contribute to the integrated control of T. castaneum.


Se evaluaron cuatro aceites esenciales (AEs) de plantas recolectadas en la selva pluvial del Chocó, Colombia, para determinar su actividad repelente e insecticida contra T. castaneum. Los AEs fueron obtenidos por hidrodestilación convencional. Las actividades repelentes e insecticidas se evaluaron por los métodos de área de preferencia y dispersión de gas, respectivamente. Las diferencias significativas (p<0,05) fueron determinadas aplicando una prueba t de student. Los AEs de Siparuna guianensis, S. conica, Piper marginatum y Nectandra acutifolia mostraron excelentes propiedades repelentes, destacando el AE de S. conicacon un 84% de repelencia (1µL/cm2), mientras que el AE de P. marginatummostró ser bioactivo a la dosis de 500 µL/mL (72 h) al inducir la mortalidad del 100% de la población expuesta. Se concluye que estas especies de plantas son fuentes naturales potencialmente viables para la producción de biorepelentes que contribuyan en el control integrado de T. castaneum.


Assuntos
Tribolium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Inseticidas/farmacologia , Colômbia , Repelentes de Insetos/farmacologia
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 36(3): 243-246, 2024 May 22.
Artigo em Chinês | MEDLINE | ID: mdl-38952309

RESUMO

The insecticide resistance is becoming increasingly severe in malaria vectors and has become one of the most important threats to global malaria elimination. Currently, malaria vectors not only have developed high resistance to conventional insecticides, including organochlorine, organophosphates, carbamates, and pyrethroids, but also have been resistant to recently used neonicotinoids and pyrrole insecticides. This article describes the current status of global insecticide resistance in malaria vectors and global insecticide resistance management strategies, analyzes the possible major challenges in the insecticide resistance management, and proposes the response actions, so as to provide insights into global insecticide resistance management and contributions to global malaria elimination.


Assuntos
Resistência a Inseticidas , Inseticidas , Malária , Animais , Humanos , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/parasitologia , Inseticidas/farmacologia , Malária/prevenção & controle , Malária/transmissão , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/parasitologia
6.
Environ Geochem Health ; 46(8): 271, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954040

RESUMO

Pyrethroids are synthetic organic insecticides. Deltamethrin, as one of the pyrethroids, has high insecticidal activity against pests and parasites and is less toxic to mammals, and is widely used in cities and urban areas worldwide. After entering the natural environment, deltamethrin circulates between solid, liquid and gas phases and enters organisms through the food chain, posing significant health risks. Increasing evidence has shown that deltamethrin has varying degrees of toxicity to a variety of organisms. This review summarized worldwide studies of deltamethrin residues in different media and found that deltamethrin is widely detected in a range of environments (including soil, water, sediment, and air) and organisms. In addition, the metabolism of deltamethrin, including metabolites and enzymes, was discussed. This review shed the mechanism of toxicity of deltamethrin and its metabolites, including neurotoxicity, immunotoxicity, endocrine disruption toxicity, reproductive toxicity, hepatorenal toxicity. This review is aim to provide reference for the ecological security and human health risk assessment of deltamethrin.


Assuntos
Inseticidas , Nitrilas , Piretrinas , Piretrinas/toxicidade , Nitrilas/toxicidade , Inseticidas/toxicidade , Humanos , Animais , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Medição de Risco , Poluentes Ambientais/toxicidade
7.
F1000Res ; 13: 226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948349

RESUMO

Objective: This scoping review will identify existing literature regarding contextual factors relevant to vector-control interventions to prevent malaria. We will use the findings of the scoping review to produce an interactive evidence and gap map. The map will assist in the priority setting, development, and conduct of targeted systematic reviews. These systematic reviews seek to assist the Vector Control and Insecticide Resistance Unit of the World Health Organization's Global Malaria Programme by informing recommendation development by their Guidelines Development Group. Introduction: Malaria contributes substantially to the global burden of disease, with an estimated 247 million cases and 619,000 deaths in 2021. Vector-control is key in reducing malaria transmission. Vector-control interventions directly target the mosquito, reducing the potential for parasite infections. These interventions commonly include insecticides used in indoor residual spraying or insecticide-treated nets and larval source management. Several new vector-control interventions are under evaluation to complement these. In addition to estimating the effects of interventions on health outcomes, it is critical to understand how populations at risk of malaria consider them in terms of their feasibility, acceptability, and values. Inclusion Criteria: Eligible studies will have assessed the contextual factors of feasibility or acceptability of the interventions of interest, or the valuation of the outcomes of interests. These assessments will be from the perspective of people who receive (residents) or deliver (workers or technicians) the vector-control intervention for the purpose of preventing malaria. Methods: We will conduct this scoping review in accordance with the JBI methodology for scoping reviews and report in line with the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews (PRISMA-ScR). We will construct the evidence and gap map following guidance from the Campbell Collaboration.


Assuntos
Malária , Controle de Mosquitos , Malária/prevenção & controle , Malária/transmissão , Humanos , Controle de Mosquitos/métodos , Animais , Inseticidas , Mosquitos Vetores
8.
BMC Microbiol ; 24(1): 231, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951812

RESUMO

BACKGROUND: Natural products are important sources for the discovery of new biopesticides to control the worldwide destructive pests Acyrthosiphon pisum Harris. Here, insecticidal substances were discovered and characterized from the secondary metabolites of the bio-control microorganism Bacillus velezensis strain ZLP-101, as informed by whole-genome sequencing and analysis. RESULTS: The genome was annotated, revealing the presence of four potentially novel gene clusters and eight known secondary metabolite synthetic gene clusters. Crude extracts, prepared through ammonium sulfate precipitation, were used to evaluate the effects of strain ZLP-101 on Acyrthosiphon pisum Harris aphid pests via exposure experiments. The half lethal concentration (LC50) of the crude extract from strain ZLP-101 against aphids was 411.535 mg/L. Preliminary exploration of the insecticidal mechanism revealed that the crude extract affected aphids to a greater extent through gastric poisoning than through contact. Further, the extracts affected enzymatic activities, causing holes to form in internal organs along with deformation, such that normal physiological activities could not be maintained, eventually leading to death. Isolation and purification of extracellular secondary metabolites were conducted in combination with mass spectrometry analysis to further identify the insecticidal components of the crude extracts. A total of 15 insecticidal active compounds were identified including iturins, fengycins, surfactins, and spergualins. Further insecticidal experimentation revealed that surfactin, iturin, and fengycin all exhibited certain aphidicidal activities, and the three exerted synergistic lethal effects. CONCLUSIONS: This study improved the available genomic resources for B. velezensis and serves as a foundation for comprehensive studies of the insecticidal mechanism by Bacillus velezensis ZLP-101 in addition to the active components within biological control strains.


Assuntos
Afídeos , Bacillus , Inseticidas , Lipopeptídeos , Animais , Afídeos/efeitos dos fármacos , Bacillus/genética , Bacillus/metabolismo , Lipopeptídeos/farmacologia , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Lipopeptídeos/isolamento & purificação , Inseticidas/farmacologia , Inseticidas/metabolismo , Inseticidas/química , Família Multigênica , Metabolismo Secundário , Controle Biológico de Vetores , Sequenciamento Completo do Genoma , Genoma Bacteriano/genética
9.
Braz J Biol ; 84: e281971, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985061

RESUMO

Producers of fish have been looking for viable alternatives for the management of Colossoma macropomum (tambaqui) in confinement systems in order to avoid the harm and subsequent losses caused by parasitic diseases. One alternative used by farmers is pesticides, such as trichlorfon, which has a genotoxic effect. Thus, this study aimed to evaluate the changes in gene expression due to the side effects of trichlorfon in tambaqui. Two treatments were used based on LC50-96h of 0.870 mg/L using 30% and 50% trichlorfon with exposure periods of 48, 72 and 96 h. For differential expression of the genes in the liver, real-time PCR was performed for the AChE, GST, CYP2J6, CYP2C8, 18S and GAPDH genes. After 96 h of exposure to trichlorfon, an alteration in the gene expression profile of the antioxidant defense system (GST) of the tambaqui was observed. It was also observed that this organophosphate did not affect the expression of genes related to the isoenzymes that are responsible for the biotransformation of xenobiotics in phase I (2J6 and 2C8) and cholinesterase AChE. It was concluded that the reduction in gene expression of GST suggests a decrease in metabolization capacity in phase II.


Assuntos
Caraciformes , Triclorfon , Animais , Triclorfon/toxicidade , Biomarcadores , Reação em Cadeia da Polimerase em Tempo Real , Poluentes Químicos da Água/toxicidade , Fígado/efeitos dos fármacos , Fatores de Tempo , Inseticidas/toxicidade
10.
PLoS One ; 19(7): e0300368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985752

RESUMO

BACKGROUND: A treated fabric device for emanating the volatile pyrethroid transfluthrin was recently developed in Tanzania that protected against night-biting Anopheles and Culex mosquitoes for several months. Here perceptions of community end users provided with such transfluthrin emanators, primarily intended to protect them against day-active Aedes vectors of human arboviruses that often attack people outdoors, were assessed in Port-au-Prince, Haiti. METHODS: Following the distribution of transfluthrin emanators to participating households in poor-to-middle class urban neighbourhoods, questionnaire surveys and in-depth interviews of end-user households were supplemented with conventional and Photovoice-based focus group discussions. Observations were assessed synthetically to evaluate user perceptions of protection and acceptability, and to solicit advice for improving and promoting them in the future. RESULTS: Many participants viewed emanators positively and several outlined various advantages over current alternatives, although some expressed concerns about smell, health hazards, bulkiness, unattractiveness and future cost. Most participants expressed moderate to high satisfaction with protection against mosquitoes, especially indoors. Protection against other arthropod pests was also commonly reported, although satisfaction levels were highly variable. Diverse use practices were reported, some of which probably targeted nocturnal Culex resting indoors, rather than Aedes attacking them outdoors during daylight hours. Perceived durability of protection varied: While many participants noted some slow loss over months, others noted rapid decline within days. A few participants specifically attributed efficacy loss to outdoor use and exposure to wind or moisture. Many expressed stringent expectations of satisfactory protection levels, with even a single mosquito bite considered unsatisfactory. Some participants considered emanators superior to fans, bedsheets, sprays and coils, but it is concerning that several preferred them to bed nets and consequently stopped using the latter. CONCLUSIONS: The perspectives shared by Haitian end-users are consistent with those from similar studies in Brazil and recent epidemiological evidence from Peru that other transfluthrin emanator products can protect against arbovirus infection. While these encouraging sociological observations contrast starkly with evidence of essentially negligible effects upon Aedes landing rates from parallel entomological assessments across Haiti, Tanzania, Brazil and Peru, no other reason to doubt the generally encouraging views expressed herein by Haitian end users could be identified.


Assuntos
Ciclopropanos , Fluorbenzenos , Controle de Mosquitos , Haiti , Animais , Humanos , Controle de Mosquitos/métodos , Feminino , Masculino , Inseticidas , Adulto , Mosquitos Vetores , Aedes/efeitos dos fármacos , Pessoa de Meia-Idade , Inquéritos e Questionários , Anopheles/efeitos dos fármacos , Culex/efeitos dos fármacos
11.
PLoS One ; 19(7): e0298512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38995958

RESUMO

Pyrethroids are the most widely used insecticides to control vector borne diseases including malaria. Physiological resistance mechanisms to these insecticides have been well described, whereas those for behavioral resistance remain overlooked. Field data suggest the presence of spatial sensory detection by Anopheles mosquitoes of the pyrethroid molecules used in insecticide-based control tools, such as long-lasting insecticide nets or insecticide residual spraying. This opens the way to the emergence of a wide range of behavioral adaptations among malaria vectors. However, the spatial sensory detection of these molecules is controversial and needs to be demonstrated. The goal of this study was to behaviorally characterize the non-contact detection of three of the most common pyrethroids used for malaria vector control: permethrin, deltamethrin an ⍺-cypermethrin. To reach this goal, we recorded the behavior (takeoff response) of Anopheles gambiae pyrethroid-sensitive and resistant laboratory strains, as well as field collected mosquitoes from the Gambiae Complex, when exposed to the headspace of bottles containing different doses of the insecticides at 25 and 35°C, in order to represent a range of laboratory and field temperatures. We found the proportion of laboratory susceptible and resistant female mosquitoes that took off was, in all treatments, dose and the temperature dependent. Sensitive mosquitoes were significantly more prone to take off only in the presence of ⍺-cypermethrin, whereas sensitive and resistant mosquitoes showed similar responses to permethrin and deltamethrin. Field-collected mosquitoes of the Gambiae Complex were also responsive to permethrin, independently of the species identity (An. gambiae, An. coluzzii and An. arabiensis) or their genotypes for the kdr mutation, known to confer resistance to pyrethroids. The observed ability of Anopheles spp. mosquitoes to detect insecticides without contact could favor the evolution of behavioral modifications that may allow them to avoid or reduce the adverse effect of insecticides and thus, the development of behavioral resistance.


Assuntos
Anopheles , Resistência a Inseticidas , Inseticidas , Controle de Mosquitos , Mosquitos Vetores , Piretrinas , Animais , Anopheles/efeitos dos fármacos , Anopheles/fisiologia , Piretrinas/farmacologia , Piretrinas/toxicidade , Inseticidas/farmacologia , Inseticidas/toxicidade , Mosquitos Vetores/efeitos dos fármacos , Controle de Mosquitos/métodos , Feminino , Nitrilas/farmacologia , Permetrina/farmacologia , Malária/transmissão , Malária/prevenção & controle
12.
Environ Geochem Health ; 46(9): 318, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001898

RESUMO

Bell peppers, a globally significant crop, face infestations from various pests. In a study, bell peppers were treated with deltamethrin, ethion, fenazaquin, and fenpropathrin at recommended and double the doses, repeated twice with a 10-day interval. The QuEChERS method underwent validation for linearity, matrix match, accuracy, and precision in bell pepper matrices for residue analysis. The limit of detection for the tested pesticides on bell peppers was 0.01 mg/L, with a quantification limit of 0.05 mg/L. Recovery studies showed a range of 94.80% to 102.80%. Initial deposits of deltamethrin, ethion, fenazaquin, and fenpropathrin on bell peppers at recommended doses were 0.371, 1.237, 0.617, and 0.640 mg/L, respectively, and at double doses were 0.712, 1.945, 1.221, and 1.189 mg/L, respectively. Safe waiting periods of 10, 11, 10, and 8 days were suggested for deltamethrin, ethion, fenazaquin, and fenpropathrin, respectively. The corresponding half-lives for the pesticides were 1.96, 1.79, 2.06, and 1.69 days, all following first-order dissipation kinetics. Dietary risk assessment indicated Hazard Quotients (HQ) below 1 and Theoretical Maximum Daily Intake (TMDI) below Acceptable Daily Intake (ADI) and Maximum Permissible Intake (MPI) levels. Therefore, at their recommended doses, the pesticides were deemed safe for bell pepper cultivation.


Assuntos
Capsicum , Contaminação de Alimentos , Inseticidas , Resíduos de Praguicidas , Piretrinas , Capsicum/química , Resíduos de Praguicidas/análise , Piretrinas/análise , Contaminação de Alimentos/análise , Cinética , Medição de Risco , Humanos , Nitrilas/toxicidade , Nitrilas/análise , Exposição Dietética
13.
Environ Geochem Health ; 46(9): 305, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001968

RESUMO

Dimethoate (DMT) is one of the most harmful and commonly used organophosphate pesticides in agricultural lands to control different groups of parasitic insects. However, this pesticide is considered a dangerous pollutant for aquatic organisms following its infiltration in coastal ecosystems through leaching. Yet, our investigation aimed to gain new insights into the toxicity mechanism of DMT in the muscles of the green crab Carcinus aestuarii, regarding oxidative stress, neurotransmission impairment, histological aspects, and changes in lipid composition, assessed for the first time on the green crab's muscle. Specimens of C. aestuarii were exposed to 50, 100, and 200 µg DMT L-1 for 24 h. Compared to the negative control group, the higher the DMT concentration, the lower the saturated fatty acids (SFA), and the higher the monounsaturated fatty acids (MUFA). The significant increase in polyunsaturated fatty acid n-6 (PUFA n-6) was related to the high release, mainly, of linoleic acid (LA, C18: 2n6) and arachidonic acid (ARA, C20: 4n6) levels. Biochemical biomarkers showed that DMT exposure promoted oxidative stress, highlighted by increased levels of hydrogen peroxide (H2O2), malondialdehyde (MDA), advanced oxidation protein product levels (AOPP), and protein carbonyl (PCO). Furthermore, the antioxidant defense system was activated, as demonstrated by the significant changes in the enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) levels associated with an adaptation process of C. aestuarii to cope with the DMT exposure. This pesticide significantly impairs the neurotransmission process, as evidenced by the inhibition of acetylcholinesterase (AChE) activity. Finally, several histopathological changes were revealed in DMT-treated crabs, including vacuolation, and muscle bundle loss.This research offered new insights into the toxic mechanism of DMT, pointing to the usefulness of fatty acid (FA) composition as a sensitive biomarker in littoral crabs.


Assuntos
Braquiúros , Dimetoato , Músculos , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Dimetoato/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Músculos/efeitos dos fármacos , Músculos/metabolismo , Ácidos Graxos/metabolismo , Inseticidas/toxicidade , Biomarcadores/metabolismo , Malondialdeído/metabolismo
14.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000265

RESUMO

Rotenone, as a common pesticide and insecticide frequently found in environmental samples, may be present in aquatic habitats worldwide. Exposure to low concentrations of this compound may cause alterations in the nervous system, thus contributing to Parkinsonian motor symptoms in both vertebrates and invertebrates. However, the effects of chronic exposure to low doses of rotenone on the activity of neurotransmitters that govern motor functions and on the specific molecular mechanisms leading to movement morbidity remain largely unknown for many aquatic invertebrates. In this study, we analyzed the effects that rotenone poisoning exerts on the activity of dopamine (DA) and acetylcholine (ACh) synthesis enzymes in the central nervous system (CNS) of Asian shore crab, Hemigrapsus sanguineus (de Haan, 1835), and elucidated the association of its locomotor behavior with Parkinson's-like symptoms. An immunocytochemistry analysis showed a reduction in tyrosine hydroxylase (TH) in the median brain and the ventral nerve cord (VNC), which correlated with the subsequent decrease in the locomotor activity of shore crabs. We also observed a variation in cholinergic neurons' activity, mostly in the ventral regions of the VNC. Moreover, the rotenone-treated crabs showed signs of damage to ChAT-lir neurons in the VNC. These data suggest that chronic treatment with low doses of rotenone decreases the DA level in the VNC and the ACh level in the brain and leads to progressive and irreversible reductions in the crab's locomotor activity, life span, and changes in behavior.


Assuntos
Braquiúros , Sistema Nervoso Central , Neurônios Colinérgicos , Neurônios Dopaminérgicos , Rotenona , Animais , Rotenona/toxicidade , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Braquiúros/efeitos dos fármacos , Braquiúros/metabolismo , Dopamina/metabolismo , Acetilcolina/metabolismo , Inseticidas/toxicidade , Tirosina 3-Mono-Oxigenase/metabolismo , Locomoção/efeitos dos fármacos
15.
Sci Rep ; 14(1): 14981, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951546

RESUMO

Gulf War Illness (GWI) describes a series of symptoms suffered by veterans of the Gulf war, consisting of cognitive, neurological and gastrointestinal dysfunctions. Two chemicals associated with GWI are the insecticide permethrin (PER) and the nerve gas prophylactic pyridostigmine-bromide (PB). In this study we assessed the effects of PER and PB exposure on the pathology and subsequent alcohol (EtOH)-induced liver injury, and the influence of a macrophage depletor, PLX3397, on EtOH-induced liver damage in PER/PB-treated mice. Male C57BL/6 mice were injected daily with vehicle or PER/PB for 10 days, followed by 4 months recovery, then treatment with PLX3397 and a chronic-plus-single-binge EtOH challenge for 10 days. PER/PB exposure resulted in the protracted increase in liver transaminases in the serum and induced chronic low-level microvesicular steatosis and inflammation in GWI vs Naïve mice up to 4 months after cessation of exposure. Furthermore, prior exposure to PER/PB also resulted in exacerbated response to EtOH-induced liver injury, with enhanced steatosis, ductular reaction and fibrosis. The enhanced EtOH-induced liver damage in GWI-mice was attenuated by strategies designed to deplete macrophages in the liver. Taken together, these data suggest that exposure to GWI-related chemicals may alter the liver's response to subsequent ethanol exposure.


Assuntos
Etanol , Camundongos Endogâmicos C57BL , Síndrome do Golfo Pérsico , Brometo de Piridostigmina , Animais , Síndrome do Golfo Pérsico/induzido quimicamente , Síndrome do Golfo Pérsico/patologia , Masculino , Brometo de Piridostigmina/farmacologia , Camundongos , Etanol/efeitos adversos , Etanol/toxicidade , Permetrina/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Inseticidas/toxicidade , Inseticidas/efeitos adversos , Modelos Animais de Doenças
17.
Mol Biol Rep ; 51(1): 800, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001994

RESUMO

BACKGROUND: Mosquitoes are widespread globally and have contributed to transmitting pathogens to humans and the burden of vector-borne diseases. They are effectively controlled at their larval stages by biocontrol agents. Unravelling natural sources for microbial agents can lead us to novel potential candidates for managing mosquito-borne diseases. In the present study, an attempt was made to isolate a novel bacterium from the field-collected agricultural soil for larvicidal activity and promising bacterial metabolites for human healthcare. METHODS AND RESULTS: Field-collected soil samples from the Union territory of Puducherry, India, have been used as the source of bacteria. Isolate VCRC B655 belonging to the genus Lysinibacillus was identified by 16S rRNA gene sequencing and exhibited promising larvicidal activity against different mosquito species, including Culex (Cx.) quinquefasciatus, Anopheles (An.) stephensi, and Aedes (Ae.) aegypti. The lethal concentration (LC) of Lysinibacillus sp. VCRCB655 was observed to be high for Cx. quiquefasciatus: LC50 at 0.047 mg/l, LC90 at 0.086 mg/l, followed by An. stephensi and Ae. aegypti (LC50: 0.6952 mg/l and 0.795 mg/l) respectively. Additionally, metabolic profiling of the culture supernatant was carried out through Gas chromatography and Mass spectrophotometry (GC/MS) and identified 15 major secondary metabolites of different metabolic classes. Diketopiperazine (DKPs), notably pyro lo [1, 2-a] pyrazine1, 4-dione, are the abundant compounds reported for antioxidant activity, and an insecticide compound benzeneacetic acid was also identified. CONCLUSIONS: A new bacterial isolate, Lysinibacillus sp. VCRC B655 has been identified with significant larvicidal activity against mosquito larvae with no observed in non-target organisms. GC-MS analysis revealed diverse bioactive compounds with substantial biological applications. In conclusion, Lysinibacillus sp. VCRC B655 showed promise as an alternative biocontrol agent for mosquito vector control, with additional biological applications further enhancing its significance.


Assuntos
Bacillaceae , Cromatografia Gasosa-Espectrometria de Massas , Larva , Controle de Mosquitos , RNA Ribossômico 16S , Animais , Bacillaceae/isolamento & purificação , Bacillaceae/metabolismo , Bacillaceae/genética , Cromatografia Gasosa-Espectrometria de Massas/métodos , Controle de Mosquitos/métodos , Larva/microbiologia , RNA Ribossômico 16S/genética , Índia , Microbiologia do Solo , Anopheles/microbiologia , Culex/microbiologia , Filogenia , Aedes/microbiologia , Inseticidas/farmacologia
18.
J Agric Food Chem ; 72(28): 15552-15560, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38950523

RESUMO

To synthesize the fundamental framework of dihydroagarofuran, a novel strategy was devised for constructing the C-ring through a dearomatization reaction using 6-methoxy-1-tetralone as the initial substrate. Subsequently, the dihydroagarofuran skeleton was assembled via two consecutive Michael addition reactions. The conjugated diene and trans-dihydroagarofuran skeleton were modified. The insecticidal activities of 33 compounds against Mythimna separata were evaluated. Compounds 11-5 exhibited an LC50 value of 0.378 mg/mL. The activity exhibited a remarkable 29-fold increase compared to positive control Celangulin V, which was widely recognized as the most renowned natural dihydroagarofuran polyol ester insecticidal active compound. Docking experiments between synthetic compounds and target proteins revealed the shared binding sites with Celangulin V. Structure-activity relationship studies indicated that methyl groups at positions C4 and C10 significantly improved insecticidal activity, while ether groups with linear chains displayed enhanced activity; in particular, the allyl ether group demonstrated optimal efficacy. Furthermore, a three-dimensional quantitative structure-activity relationship model was established to investigate the correlation between the skeletal structure and activity. These research findings provide valuable insights for discovering and developing dihydroagarofuran-like compounds.


Assuntos
Inseticidas , Simulação de Acoplamento Molecular , Mariposas , Inseticidas/química , Inseticidas/farmacologia , Inseticidas/síntese química , Animais , Mariposas/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Relação Quantitativa Estrutura-Atividade , Lignanas/química , Lignanas/farmacologia , Sesquiterpenos
19.
J Agric Food Chem ; 72(28): 15624-15632, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38952111

RESUMO

Phytophagous insects are more predisposed to evolve insecticide resistance than other insect species due to the "preadaptation hypothesis". Cytochrome P450 monooxygenases have been strongly implicated in insecticide and phytochemical detoxification in insects. In this study, RNA-seq results reveal that P450s of Spodoptera litura, especially the CYP3 clan, are dominant in cyantraniliprole, nicotine, and gossypol detoxification. The expression of a Malpighian tubule-specific P450 gene, SlCYP9A75a, is significantly upregulated in xenobiotic treatments except α-cypermethrin. The gain-of-function and loss-of-function analyses indicate that SlCYP9A75a contributes to cyantraniliprole, nicotine, and α-cypermethrin tolerance, and SlCYP9A75a is capable of binding to these xenobiotics. This study indicates the roles of inducible SlCYP9A75a in detoxifying man-made insecticides and phytochemicals and may provide an insight into the development of cross-tolerance in omnivorous insects.


Assuntos
Sistema Enzimático do Citocromo P-450 , Proteínas de Insetos , Resistência a Inseticidas , Inseticidas , Túbulos de Malpighi , Spodoptera , Xenobióticos , Animais , Spodoptera/genética , Spodoptera/efeitos dos fármacos , Spodoptera/enzimologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Xenobióticos/metabolismo , Inseticidas/farmacologia , Túbulos de Malpighi/metabolismo , Túbulos de Malpighi/enzimologia , Túbulos de Malpighi/efeitos dos fármacos , Resistência a Inseticidas/genética , Inativação Metabólica/genética , Larva/crescimento & desenvolvimento , Larva/genética , Larva/efeitos dos fármacos
20.
Environ Sci Pollut Res Int ; 31(32): 44908-44919, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38955973

RESUMO

The honey bee Apis mellifera plays a significant role as a pollinator of native and cultivated plants, by increasing the productivity of several cultures, preserving the flora, and producing forest seeds. However, bee populations are declining worldwide, including A. mellifera, due to Colony Collapse Disorder, mainly resulting from the constant use of pesticides in the crops. Teflubenzuron is a physiological insecticide that belongs to the benzoylurea group, which inhibits chitin synthesis, the main component of the insect integument classified as safe for non-target insects, including bees. However, its effect on non-target organs of insects remains unknown. The midgut is the main organ of the digestive tract, which works in digestion and absorption and may be exposed to pesticides that contaminate food resources. The present work aimed to verify if the insecticide teflubenzuron is toxic and has histopathological effects on the midgut of A. mellifera adult workers. Workers exposed orally and chronically to the field-realistic concentration of teflubenzuron present 81.54% mortality. The epithelium of the midgut of these bees presents high vacuolization, spherocrystals, cell fragments released to the organ lumen, apocrine secretion, nuclear pyknosis, loss of cell-cell contact, and damage to regenerative cell nests and to the peritrophic matrix. These results indicate that the chitin synthesis-inhibiting insecticide teflubenzuron is toxic to A. mellifera after chronic oral exposure, at realistic field concentration, although it is classified as non-toxic to adult and non-target insects.


Assuntos
Benzamidas , Inseticidas , Animais , Abelhas/efeitos dos fármacos , Inseticidas/toxicidade , Benzamidas/toxicidade , Praguicidas/toxicidade
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