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1.
J Agric Food Chem ; 67(36): 9979-9988, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31411878

RESUMO

A delta class glutathione S-transferase gene (BoGSTd2) is identified from Bradysia odoriphaga for the first time. Developmental expression analysis showed that expression of BoGSTd2 is significantly higher in the fourth instar larval stage and the adult stage. Tissue-specific expression analysis found that BoGSTd2 was expressed predominantly in the midgut and Malpighian tubules in the fourth instar larvae and the abdomen of adults. Expression of BoGSTd2 was significantly upregulated following exposure to chlorpyrifos and clothianidin. In vitro inhibition and metabolic assays indicated that recombinant BoGSTd2 could not directly metabolize chlorpyrifos and clothianidin. Nevertheless, disk diffusion assays indicated that BoGSTd2 plays an important role in protection against oxidative stress. RNAi assays showed that BoGSTd2 participates in the elimination of reactive oxygen species induced by chlorpyrifos and clothianidin. These results strongly suggest that BoGSTd2 plays an important role in chlorpyrifos and clothianidin detoxification in B. odoriphaga by protecting tissues from oxidative stress induced by these insecticides.


Assuntos
Dípteros/enzimologia , Glutationa Transferase/metabolismo , Proteínas de Insetos/metabolismo , Inseticidas/metabolismo , Animais , Clorpirifos/metabolismo , Dípteros/genética , Dípteros/crescimento & desenvolvimento , Dípteros/metabolismo , Glutationa Transferase/genética , Guanidinas/metabolismo , Inativação Metabólica , Proteínas de Insetos/genética , Larva/enzimologia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Neonicotinoides/metabolismo , Estresse Oxidativo , Tiazóis/metabolismo
2.
Pestic Biochem Physiol ; 159: 41-50, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400783

RESUMO

Emerging fungal phytodiseases are a food security threat and novel fungicides are in an urgent need. Herein, a series of isobutyrophenone derivatives were designed and synthesized. The derivatives exhibited excellent fungicidal activities against seven fungi. The structure-activity relationship (SAR) study indicated that the introduction of a bromo group at the position 3 or 5 of the phenyl ring, as well as esterification of the 4-hydroxy with a chloroacetyl group, could substantially increase the antifungal activity and spectrum of the compounds. Among all 23 compounds, 2-bromo-3-hydroxy-4-isobutyryl-6-methylphenyl 2-chloroacetate (12b) showed the highest fungicidal activity against all seven tested fungal pathogens with EC50 values ranging from 1.22 to 39.94 µg/mL and exhibited the most potent inhibition against class II fructose-1,6-bisphosphate aldolase with an IC50 of 3.63 µM. The lead compounds were proven to be safe to NIH3T3/293 T cells and silkworm larvae, and relatively stable under different harsh conditions. Detached fruit tests showed the practical potential of lead compounds for fruit (or plant) protection. Taken together, our results indicated that the isobutyrophenone derivatives could be further optimized and developed as advanced leads for new fungicides.


Assuntos
Antifúngicos/química , Antifúngicos/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Animais , Bombyx/metabolismo , Linhagem Celular , Frutose-Bifosfato Aldolase/genética , Humanos , Larva/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Células NIH 3T3 , Relação Estrutura-Atividade
3.
Pestic Biochem Physiol ; 159: 85-90, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400788

RESUMO

RNA interference (RNAi) is a potentially useful pest control method because of its high specificity. Silencing the expression of important RNAi target genes of pests will block important biological processes and reduce pest damage. Ecdysone is a unique arthropod hormone and the ecdysone receptor (EcR) is a key factor in molting pathway. We investigated the possibility that dsRNA targeting of the EcR of Tetranychus cinnabarinus (TcEcR) could effectively block development from larvae to adults. The mRNA level of TcEcR was highest in the larva stage, and 73.1% of the mites failed to survive the larva stage when TcEcR expression was silenced. Only 11.7% of T. cinnabarinus ingesting dsRNA successfully developed into adults, while 86.7% in the control succeeded in molting across each stage. RNAi significantly increased the developmental intervals of T. cinnabarinus. Under the effects of dsRNA, development times for the larva and first nymph doubled. Phenotype of body size change and death were observed during the development of T. cinnabarinus ingesting dsRNA. These findings suggest that RNAi is a potential means for the control of T. cinnabarinus. Genes in hormone pathways such as EcR are possible RNAi targets.


Assuntos
Larva/metabolismo , Interferência de RNA/fisiologia , Receptores de Esteroides/metabolismo , Tetranychidae/metabolismo , Animais , Tamanho Corporal , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , RNA de Cadeia Dupla/genética , Receptores de Esteroides/genética , Tetranychidae/crescimento & desenvolvimento
4.
Ecotoxicol Environ Saf ; 182: 109380, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279279

RESUMO

Ultraviolet (UV) is an omnipresent environmental carcinogen transmitted by sunlight. Excessive UV irradiation has been correlated to an increased risk of skin cancers. UVB, the most mutagenic component among the three UV constituents, causes damage mainly through inducing DNA damage and oxidative stress. Therefore, strategies or nutrients that strengthen an individual's resistance to UV-inflicted harmful effects shall be beneficial. Folate is a water-soluble B vitamin essential for nucleotides biosynthesis, and also a strong biological antioxidant, hence a micronutrient with potential of modulating individual's vulnerability to UV exposure. In this study, we investigated the impact of folate status on UV sensitivity and the protective activity of folate supplementation using a zebrafish model. Elevated reactive oxygen species (ROS) level and morphological injury were observed in the larvae exposed to UVB, which were readily rescued by supplementing with folic acid, 5-formyltetrahydrofolate (5-CHO-THF) and N-acetyl-L-cysteine (NAC). The UVB-inflicted abnormalities and mortality were worsened in Tg(hsp:EGFP-γGH) larvae displaying folate deficiency. Intriguingly, only supplementation with 5-CHO-THF, as opposed to folic acid, offered significant and consistent protection against UVB-inflicted oxidative damage in the folate-deficient larvae. We concluded that the intrinsic folate status correlates with the vulnerability to UVB-induced damage in zebrafish larvae. In addition, 5-CHO-THF surpassed both folic acid and NAC in preventing UVB-inflicted oxidative stress and injury in our current experimental zebrafish model.


Assuntos
Deficiência de Ácido Fólico/prevenção & controle , Leucovorina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Complexo Vitamínico B/farmacologia , Peixe-Zebra/metabolismo , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Suplementos Nutricionais , Deficiência de Ácido Fólico/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
5.
Ecotoxicol Environ Saf ; 182: 109406, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31288122

RESUMO

Obesity, a risk factor for the development of type-2 diabetes, hypertension, cardiovascular disease, hepatic steatosis and some cancers, has been ranked in the top 10 health risk in the world by the World Health Organization. Despite the growing body of literature evidencing an association between the obesity epidemic and specific chemical exposure across a wide range of animal taxa, very few studies assessed the effects of chemical mixtures and environmental samples on lipid homeostasis. Additionally, the mode of action of several chemicals reported to alter lipid homeostasis is still poorly understood. Aiming to fill some of these gaps, we combined an in vivo assay with the model species zebrafish (Danio rerio) to screen lipid accumulation and evaluate expression changes of key genes involved in lipid homeostasis, alongside with an in vitro transactivation assay using human and zebrafish nuclear receptors, retinoid X receptor α and peroxisome proliferator-activated receptor γ. Zebrafish larvae were exposed from 4 th day post-fertilization until the end of the experiment (day 18), to six different treatments: experimental control, solvent control, tributyltin at 100 ng/L Sn and 200 ng/L Sn (positive control), and wastewater treatment plant influent at 1.25% and 2.5%. Exposure to tributyltin and to 2.5% influent led to a significant accumulation of lipids, with white adipose tissue deposits concentrating in the perivisceral area. The highest in vitro tested influent concentration (10%) was able to significantly transactivate the human heterodimer PPARγ/RXRα, thus suggesting the presence in the influent of HsPPARγ/RXRα agonists. Our results demonstrate, for the first time, the ability of complex environmental samples from a municipal waste water treatment plant influent to induce lipid accumulation in zebrafish larvae.


Assuntos
Larva/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/induzido quimicamente , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Relação Dose-Resposta a Droga , Homeostase , Humanos , Larva/metabolismo , Obesidade/metabolismo , Águas Residuárias/química , Purificação da Água
6.
Ecotoxicol Environ Saf ; 182: 109446, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31323523

RESUMO

Increased use of sugarcane pesticides and their destination to non-target environments in Brazil has generated concerns related to the conservation of more vulnerable groups, such as amphibians. Besides the high skin permeability, tadpoles are constantly restricted to small and ephemeral ponds, where exposure to high concentrations of pesticides in agricultural areas is inevitable. This study evaluated chronic effects caused by sub-lethal concentrations of 2,4-dichlorophenoxyacetic acid herbicide on energy storage, development, respiration rates, swimming performance and avoidance behavior of bullfrog tadpoles (Lithobates catesbeianus). Firstly, we conducted acute toxicity test (96 h) to estipulate sub-lethal concentrations of 2,4-D and evaluate the sensitivity of three tadpoles' species to this herbicide. Results showed that Leptodactylus fuscus presented the lowest LC50 96 h, 28.81 mg/L, followed by Physalaemus nattereri (143.08 mg/L) and L. catesbeianus (574.52 mg/L). Chronic exposure to 2,4-D (125, 250 and 500 µg/L) delayed metamorphosis and inhibited the growth of tadpoles at concentrations of 125 µg/L. Effects on biochemical reserves showed that 2,4-D increased total hepatic lipids in tadpoles, although some individual lipid classes (e.g. free fatty acids and triglycerides) were reduced. Protein and carbohydrates contents were also impaired by 2,4-D, suggesting a disruption on energy metabolism of amphibians by the herbicide. In addition to biochemical changes, respiration rates and swimming speed were also decreased after chronic exposure to 2,4-D, and these responses appeared to be correlated with the changes detected in the basic energy content. Avoidance test indicated that tadpoles of L. catesbeinus avoided the presence of 2,4-D, however they were unable to detect increasing gradients of the contaminant. Our data showed that chronic exposure to 2,4-D impaired biochemical, physiological and behavioral aspects of tadpoles, which may compromise their health and make them more vulnerable to environmental stressors in natural systems.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Aprendizagem da Esquiva/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Herbicidas/toxicidade , Larva/efeitos dos fármacos , Taxa Respiratória/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Relação Dose-Resposta a Droga , Larva/metabolismo , Metamorfose Biológica/efeitos dos fármacos , Rana catesbeiana , Natação , Testes de Toxicidade Aguda
7.
J Agric Food Chem ; 67(32): 8896-8904, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31339308

RESUMO

The mosquito Aedes aegypti is associated with the spread of many viral diseases in humans, including Dengue virus (DENVs), Yellow fever virus (YFV), Zika virus (ZIKV), and Chikungunya virus (CHIKV). Bacillus thuringiensis (Bt) is widely used as a biopesticide, which produces Cry toxins for mosquito control. The Cry toxins bind mainly to important receptors, including alkaline phosphatase (ALP) and aminopeptidase-N (APN). This work investigated the function of a C-type lectin, CTLGA9, in A. aegypti in response to Cry toxins. Our results showed by far-western blot and ELISA methods that the CTLTGA9 protein interacted with brush border membrane vesicles (BBMVs) of A. aegypti larvae and with ALP1, APN, and Cry11Aa proteins. Furthermore, molecular docking showed overlapping binding sites in ALP1 and APN for binding to Cry11Aa and CTLGA9. The toxicity assays further demonstrated that CTLGA9 inhibited the larvicidal activity of Cry toxins. According to the results of molecular docking, CTLGA9 may compete with Cry11Aa for binding to ALP1 and APN receptors and thus decreases the mosquitocidal toxicity of Cry11Aa. Our results provide further insights into better understanding the mechanism of Cry toxins and help improve the Cry toxicity for mosquito control.


Assuntos
Aedes/efeitos dos fármacos , Aedes/metabolismo , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Proteínas de Insetos/metabolismo , Aedes/química , Aedes/genética , Animais , Proteínas de Bactérias/química , Sítios de Ligação , Endotoxinas/química , Proteínas Hemolisinas/química , Proteínas de Insetos/química , Proteínas de Insetos/genética , Larva/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos
8.
Parasit Vectors ; 12(1): 339, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292008

RESUMO

BACKGROUND: The primary cause of parasitic gastroenteritis in small ruminants in temperate regions is the brown stomach worm, Teladorsagia circumcincta. Host immunity to this parasite is slow to develop, consistent with the ability of T. circumcincta to suppress the host immune response. Previous studies have shown that infective fourth-stage T. circumcincta larvae produce excretory-secretory products that are able to modulate the host immune response. The objective of this study was to identify immune modulatory excretory-secretory proteins from populations of fourth-stage T. circumcincta larvae present in two different host-niches: those associated with the gastric glands (mucosal-dwelling larvae) and those either loosely associated with the mucosa or free-living in the lumen (lumen-dwelling larvae). RESULTS: In this study excretory-secretory proteins from mucosal-dwelling and lumen-dwelling T. circumcincta fourth stage larvae were analysed using comparative 2-dimensional gel electrophoresis. A total of 17 proteins were identified as differentially expressed, with 14 proteins unique to, or enriched in, the excretory-secretory proteins of mucosal-dwelling larvae. One of the identified proteins, unique to mucosal-dwelling larvae, was a putative peroxiredoxin (T. circumcincta peroxiredoxin 1, Tci-Prx1). Peroxiredoxin orthologs from the trematode parasites Schistosoma mansoni and Fasciola hepatica have previously been shown to alternatively activate macrophages and play a key role in promoting parasite induced Th2 type immunity. Here we demonstrate that Tci-Prx1 is expressed in all infective T. circumcincta life-stages and, when produced as a recombinant protein, has peroxidase activity, whereby hydrogen peroxide (H2O2) is reduced and detoxified. Furthermore, we use an in vitro macrophage stimulation assay to demonstrate that, unlike peroxiredoxins from trematode parasites Schistosoma mansoni and Fasciola hepatica, Tci-Prx1 is unable to alternatively activate murine macrophage cells. CONCLUSIONS: In this study, we identified differences in the excretory-secretory proteome of mucosal-dwelling and lumen-dwelling infective fourth-stage T. circumcincta larvae, and demonstrated the utility of this comparative proteomic approach to identify excretory-secretory proteins of potential importance for parasite survival and/or host immune modulation.


Assuntos
Proteínas de Helminto/metabolismo , Peroxirredoxinas/metabolismo , Trichostrongyloidea/metabolismo , Animais , Eletroforese em Gel Bidimensional , Proteínas de Helminto/genética , Interações Hospedeiro-Parasita , Peróxido de Hidrogênio/metabolismo , Enteropatias Parasitárias , Larva/imunologia , Larva/metabolismo , Camundongos , Membrana Mucosa/parasitologia , Peroxirredoxinas/genética , Proteoma/análise , Proteômica , Ovinos/parasitologia , Doenças dos Ovinos/parasitologia , Trichostrongyloidea/imunologia
9.
Aquat Toxicol ; 213: 105227, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31226596

RESUMO

The environmental impact of exposure to 3D-printed plastics as well as potential migration of toxic chemicals from 3D-printed plastics remains largely unexplored. In this work we applied leachates from plastics fabricated using a stereolithography (SLA) process to early developmental stages of zebrafish (Danio rerio) to investigate developmental toxicity and neurotoxicity. Migration of unpolymerized photoinitiator, 1-hydroxycyclohexyl phenyl ketone (1-HCHPK) from a plastic solid phase to aqueous media at up to 200 mg/L in the first 24 h was detected using gas chromatography-mass spectrometry. Both plastic extracts (LC50 22.25% v/v) and 1-HCHPK (LC50 60 mg/L) induced mortality and teratogenicity within 48 h of exposure. Developmental toxicity correlated with in situ generation of reactive oxygen species (ROS), an increase in lipid peroxidation and protein carbonylation markers and enhanced activity of superoxide dismutase (SOD) and glutathione-S-transferase (GST) in embryos exposed to concentrations as low as 20% v/v for plastic extracts and 16 mg/L for 1-HCHPK. ROS-induced cellular damage led to induction of caspase-dependent apoptosis which could be pharmacologically inhibited with both antioxidant ascorbic acid and a pan-caspase inhibitor. Neuro-behavioral analysis showed that exposure to plastic leachates reduced spontaneous embryonic movement in 24-36 hpf embryos. Plastic extracts in concentrations above 20% v/v induced rapid retardation of locomotion, changes in photomotor response and habituation to photic stimuli with progressive paralysis in 120 hpf larvae. Significantly decreased acetylcholinesterase (AChE) activity with lack of any CNS-specific apoptotic phenotypes as well as lack of changes in motor neuron density, axonal growth, muscle segment integrity or presence of myoseptal defects were detected upon exposure to plastic extracts during embryogenesis. Considering implications of the results for environmental risk assessment and the growing usage of 3D-printing technologies, we speculate that some 3D-printed plastic waste may represent a significant and yet very poorly uncharacterized environmental hazard that merits further investigation on a range of aquatic and terrestrial species.


Assuntos
Comportamento Animal , Sistema Nervoso/efeitos dos fármacos , Plásticos/toxicidade , Impressão Tridimensional , Testes de Toxicidade , Peixe-Zebra/fisiologia , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Biomarcadores/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Glutationa Transferase/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Desenvolvimento Muscular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia
10.
Environ Sci Pollut Res Int ; 26(23): 23242-23256, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31190300

RESUMO

The aim of this study was to verify the effects of the isolated forms of Boral® SC 500, Glifosato® Biocarb herbicides, and a blend of both herbicides on metabolism and oxidative balance markers of Rana catesbeiana tadpoles and on their nutritional condition. Groups of tadpoles were divided into different treatments: control (no herbicides), Boral® 500 SC (sulfentrazone: 130 µg/L), Glifosato® Biocarb (glyphosate: 234 µg/L), and a blend of both herbicides. After 7 days, the liver, caudal muscle, and blood samples were taken to subsequently perform the biomarkers determination by spectrophotometry. The intestinal condition factor increased in animals exposed to glyphosate and herbicide blends, suggesting a hyperphagic effect. This hypothesis was confirmed by the rise of triglycerides and circulating very low-density lipoprotein (VLDL). There was a significant increase in the levels of uric acid in tadpoles exposed to the herbicide blend. Corticosterone levels reduced significantly in animals exposed to glyphosate and the herbicide blend. Oxidative stress markers had a tissue-dependent response. In the liver, glutathione S-transferase increased, and superoxide dismutase and catalase decreased in animals exposed to sulfentrazone and glyphosate. Lipoperoxidation was reduced in the glyphosate treatment. In the caudal muscle, superoxide dismutase and catalase activities were maintained, and there was a decline in the levels of glutathione S-transferase and TBARS only in the blend group.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Larva/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sulfonamidas/toxicidade , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Relação Dose-Resposta a Droga , Glicina/metabolismo , Glicina/toxicidade , Herbicidas/metabolismo , Larva/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Rana catesbeiana , Sulfonamidas/metabolismo , Triazóis/metabolismo , Poluentes Químicos da Água/metabolismo
11.
J Insect Sci ; 19(3)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31237955

RESUMO

Farming insects has recently emerged as a new source of protein and lipid production. To date, research has mostly focused on food applications of insects. Focusing on nonfood potential of oil and proteins of insects, high-throughput studies of insect lipids and proteins are needed. We performed proteomics and lipidomics investigation on black soldier fly (Hermitia illucens) and blow fly (Lucilia sericata) larvae to investigate new potential and applications. We used mass spectrometry for proteomics and lipidomics analysis of control and treated larvae. Treatment was performed by incubation with a biological decomposer. We provide the list of all fatty acids with their concentration in control and treated larvae. This result showed high levels of lauric acid in black soldier fly, which could even increase after biological decomposition. Proteomics analysis showed the presence of proteins like collagen of cosmetic interest, and proteins with antimicrobial properties such as phenoloxidases and enzymatic activities, such as amylase and trypsin. Insects harbor high potential for nonfood usage as additives, antimicrobial effects, and even pharmaceuticals and cosmetics. These data open avenues for future research in pharmacological and cosmetic approaches to find new molecules of interests.


Assuntos
Dípteros/metabolismo , Metabolismo dos Lipídeos , Proteoma , Animais , Anti-Infecciosos/análise , Dípteros/química , Dípteros/genética , Proteínas de Insetos/análise , Larva/química , Larva/metabolismo , Lipídeos/análise , Proteômica
12.
Pestic Biochem Physiol ; 157: 211-218, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153471

RESUMO

Herbivore attack leads to enhanced production of defensive compounds to mount anti-herbivore defense in plants via activation of the jasmonate signaling pathway. On the other hand, some herbivores can eavesdrop on plants defense signaling and up-regulate their cytochrome P450 genes to increase detoxification of defensive compounds. However, the ecological risk of eavesdropping on plant defense signaling is largely unknown. In this study, we examined the induction of cytochrome P450s by methyl jasmonate (MeJA) and its consequence on the toxicity of aflatoxin B1 (AFB1) to Helicoverpa armigra larvae. The results show that MeJA applications either in a diet or volatile exposure enhanced the toxicity of AFB1 to the larvae. RNA sequences analysis revealed that cytochrome P450 CYP6AE19 was highly induced when MeJA was applied with AFB1. In addition, HaGST encoding glutathione-S-transferase that mainly transforms aflatoxin B1 exo-8,9-epoxide to aflatoxin B1 exo-8,9-glutathione was also induced. RNA interference of CYP6AE19 via injecting a double-stranded RNA decreased mortality of larvae exposed to AFB1; while injecting a double-stranded RNA of HaGST increased larval mortality. Furthermore, a protein model was generated and a subsequent docking simulation for AFB1 suggests the bioactivation as a major mechanism of AFB1. This study provides evidence that MeJA increased larval mortality of H. armigera via induction of CYP6AE19 that can bioactivate AFB1.


Assuntos
Acetatos/farmacologia , Aflatoxina B1/metabolismo , Ciclopentanos/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Mariposas/efeitos dos fármacos , Mariposas/metabolismo , Oxilipinas/farmacologia , Animais , Larva/efeitos dos fármacos , Larva/metabolismo , Oxirredução/efeitos dos fármacos
13.
J Chem Ecol ; 45(7): 598-609, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218595

RESUMO

Insect herbivory induces plant defense responses that are often modulated by components in insect saliva, oral secretions or regurgitant, frass, or oviposition fluids. These secretions contain proteins and small molecules that act as elicitors or effectors of plant defenses. Several non-protein elicitors have been identified from insect oral secretions, whereas studies of insect saliva have focused mainly on protein identification. Yet, insect saliva may also contain non-protein molecules that could activate defense responses in plants. The goal of this study was to identify non-protein plant defense elicitors present in insect saliva. We used the fall armyworm (FAW), Spodoptera frugiperda and its host plants tomato, maize, and rice as a model system. We tested the effect of protein-digested saliva or non-protein components on herbivore-induced defense responses in maize, rice and tomato. We identified phytohormones in FAW saliva using high performance liquid chromatography coupled with mass spectrometry. The results of this study show that non-protein components in FAW saliva modulated defense responses in different plant species. The saliva of this insect contains benzoic acid, and the phytohormones jasmonic acid, salicylic acid, and abscisic acid at concentrations of <5 ng per µl of saliva. Plant treatment with similar phytohormone quantities detected in FAW saliva upregulated the expression of a maize proteinase inhibitor gene in maize, and down-regulated late herbivore-induced defenses in tomato plants. We conclude that FAW saliva is a complex fluid that, in addition to known enzymatic plant defense elicitors, contains phytohormones and other small molecules.


Assuntos
Reguladores de Crescimento de Planta/análise , Saliva/química , Zea mays/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Herbivoria , Larva/metabolismo , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Espectrometria de Massas , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saliva/metabolismo , Spodoptera/crescimento & desenvolvimento , Zea mays/parasitologia
14.
Chemosphere ; 233: 579-589, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31195263

RESUMO

Complex interactions have been established between nanoparticles (NPs) and heavy metals in real environments. Herein we used zebrafish embryos to investigate the influence of titanium dioxide NPs (n-TiO2) on the uptake, bioconcentration, and depuration, and toxicity of Pb. The formation of n-TiO2-Pb complexes was confirmed in an exposure suspension. An increase in Pb bioconcentration was observed in zebrafish embryos upon co-exposure to n-TiO2 and Pb; moreover, n-TiO2-Pb complexes could be found in the embryos, indicating the bioavailability of NPs. However, there was no difference in the depuration rates of Pb in the presence of n-TiO2. Metallothionein (MT) content was significantly increased upon exposure to Pb alone, and the content significantly increased even further upon co-exposure. A downregulation in the expression levels of the neurodevelopment-related genes gfap, syn2α, and elavl3 was observed in the embryos, and we also noted a reduction in the swimming speed of and the total distance traveled by the larvae. To summarize, our results indicate that n-TiO2 can act as an effective carrier of Pb to enhance its uptake, bioavailability, and toxicity in zebrafish embryos.


Assuntos
Embrião não Mamífero/fisiologia , Chumbo/toxicidade , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Disponibilidade Biológica , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Larva/metabolismo , Metalotioneína/metabolismo , Nanopartículas/toxicidade , Peixe-Zebra/metabolismo
15.
PLoS Negl Trop Dis ; 13(5): e0007422, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31107878

RESUMO

New mosquito control strategies are vitally needed to address established and emerging arthropod-borne infectious diseases. Here we describe the characterization of a yeast interfering RNA larvicide that was developed through the genetic engineering of Saccharomyces cerevisiae (baker's yeast) to express a short hairpin RNA targeting the Aedes aegypti synaptotagmin (Aae syt) gene. The larvicide effectively silences the Aae syt gene, causes defects at the larval neural synapse, and induces high rates of A. aegypti larval mortality in laboratory, simulated-field, and semi-field trials. Conservation of the interfering RNA target site in multiple mosquito species, but not in humans or other non-target species, suggested that it may function as a broad-range mosquito larvicide. In support of this, consumption of the yeast interfering RNA larvicide was also found to induce high rates of larval mortality in Aedes albopictus, Anopheles gambiae, and Culex quinquefasciatus mosquito larvae. The results of these studies suggest that this biorational yeast interfering RNA larvicide may represent a new intervention that can be used to combat multiple mosquito vectors of human diseases.


Assuntos
Proteínas de Insetos/genética , Controle de Mosquitos/métodos , Mosquitos Vetores/genética , Controle Biológico de Vetores/métodos , Interferência de RNA , Saccharomyces cerevisiae/genética , Sinaptotagminas/genética , Aedes/genética , Aedes/metabolismo , Aedes/microbiologia , Animais , Anopheles/genética , Anopheles/metabolismo , Anopheles/microbiologia , Culex/genética , Culex/metabolismo , Culex/microbiologia , Feminino , Engenharia Genética , Proteínas de Insetos/metabolismo , Larva/genética , Larva/metabolismo , Larva/virologia , Masculino , Mosquitos Vetores/metabolismo , Mosquitos Vetores/virologia , Saccharomyces cerevisiae/metabolismo , Sinaptotagminas/metabolismo
16.
Environ Pollut ; 251: 600-608, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31108293

RESUMO

Changing light conditions due to human activities represents an important emerging environmental concern. Although changes to natural light conditions can be independently detrimental, in nature, organisms commonly face multiple stressors. To understand the consequences of altered light conditions, we exposed a model amphibian (wood frog; Lithobates sylvaticus) to a control and two anthropogenic light conditions: intensified daytime illuminance and artificial light at night - ALAN (intensified daytime illuminance + extended photoperiod). We measured (1) metrics of fitness (hatching success as well as survival to, size at, and time to metamorphosis) (2) susceptibility (time to death) to a commonly co-occurring anthropogenic stressor, road salt (NaCl) and (3) susceptibility (infection load) to a common parasite (trematode). We also explored behavioral (swimming activity) and physiological (baseline corticosterone (CORT) release rates) changes induced by these light conditions, which may mediate changes in the other measured parameters. We found that both intensified daytime illuminance and ALAN reduced hatching success. In contrast, for amphibians that successfully hatched, neither treatment affected amphibian survival or time to metamorphosis but individuals exposed to ALAN were larger at metamorphosis. The light treatments also had marginal effects; individuals in ALAN treatments were more susceptible to NaCl and trematodes. Finally, tadpoles exposed to ALAN moved significantly less than tadpoles in the control and intensified daytime illuminance treatments, while light had no effect on CORT release rate. Overall, changes in light conditions, in particular ALAN, significantly impacted an amphibian model in laboratory conditions. This work underscores the importance of considering not only the direct effects of light on fitness metrics but also the indirect effects of light with other abiotic and biotic stressors. Anthropogenic-induced changes to light conditions are expected to continue increasing over time so understanding the diverse consequences of shifting light conditions will be paramount to protecting wildlife populations.


Assuntos
Larva/efeitos da radiação , Luz , Metamorfose Biológica/efeitos da radiação , Fotoperíodo , Ranidae/crescimento & desenvolvimento , Trematódeos/crescimento & desenvolvimento , Animais , Corticosterona/metabolismo , Humanos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/parasitologia , Ranidae/metabolismo , Ranidae/parasitologia
17.
Dev Genes Evol ; 229(4): 89-102, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31041506

RESUMO

The Wnt/beta-catenin pathway has many key roles in the development of animals, including a conserved and central role in the specification of the primary (antero-posterior) body axis. The posterior expression of Wnt ligands and the anterior expression of secreted Wnt inhibitors are known to be conserved during the larval metamorphosis of tapeworms. However, their downstream signaling components for Wnt/beta-catenin signaling have not been characterized. In this work, we have studied the core components of the beta-catenin destruction complex of the human pathogen Echinococcus multilocularis, the causative agent of alveolar echinococcosis. We focused on two Axin paralogs that are conserved in tapeworms and other flatworm parasites. Despite their divergent sequences, both Axins could robustly interact with one E. multilocularis beta-catenin paralog and limited its accumulation in a heterologous mammalian expression system. Similarly to what has been described in planarians (free-living flatworms), other beta-catenin paralogs showed limited or no interaction with either Axin and are unlikely to function as effectors in Wnt signaling. Additionally, both Axins interacted with three divergent GSK-3 paralogs that are conserved in free-living and parasitic flatworms. Axin paralogs have highly segregated expression patterns along the antero-posterior axis in the tapeworms E. multilocularis and Hymenolepis microstoma, indicating that different beta-catenin destruction complexes may operate in different regions during their larval metamorphosis.


Assuntos
Proteína Axina/genética , Complexo de Sinalização da Axina/genética , Echinococcus multilocularis/genética , Quinase 3 da Glicogênio Sintase/genética , Proteínas de Helminto/genética , Hymenolepis/genética , beta Catenina/genética , Sequência de Aminoácidos , Animais , Proteína Axina/química , Proteína Axina/metabolismo , Complexo de Sinalização da Axina/química , Echinococcus multilocularis/crescimento & desenvolvimento , Echinococcus multilocularis/metabolismo , Perfilação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas de Helminto/química , Humanos , Hymenolepis/crescimento & desenvolvimento , Hymenolepis/metabolismo , Larva/metabolismo , Filogenia , Alinhamento de Sequência , beta Catenina/metabolismo
18.
Environ Sci Pollut Res Int ; 26(18): 18509-18519, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049864

RESUMO

Polyethylene (PE) is one of the major persistent plastic that is not biodegradable at considerable rates in most environments, and is the major source of unceasing environmental pollution. Recently, biodegradation of plastic wastes through waxworms and mealworms were reported. The present study focuses on the high-density polyethylene (HDPE) degradation capabilities of the larvae of Achroia grisella (lesser waxworm) and its ability to complete its life cycle when fed with HDPE. Effects of added nutrition on PE degradation were assessed, providing wax comb as co-feed (PE-WC). The egested frass of the waxworm fed on waxcomb (WC), PE, and PE-WC were studied by analyzing the changes in physiochemical properties through FTIR and 1H NMR techniques in addition to weight loss percentage of PE and survival rates of the tested lesser waxworms. The post-degradation studies of WC and PE showed 90.5 ± 1.2% and 43.3 ± 1.6% weight loss, respectively, by a group of 100 lesser waxworms. Over an 8-day period, PE consumption increased with an ingestion of 1.83 mg of PE per day per larvae. Supplementing the PE feed of lesser waxworms with WC facilitated enhanced PE degradation showing 69.6 ± 3.2% weight loss. Twenty-eight day survival rates for lesser waxworms fed on WC, PE, and PE-WC were 91.3 ± 1.01%, 74.6 ± 2.9%, and 86 ± 1.4%, respectively. The FTIR and 1H NMR analysis of egested frass indicated formation of new functional organic groups, supporting biodegradation of PE in lesser waxworms. The frass of the lesser waxworm fed on PE samples shows the presence of new carbonyl and alcoholic groups with increase in unsaturated hydrocarbon indicating formation of biodegraded intermediates. Lesser waxworms fed with WC, PE, and PE-WC completed all life cycle stages (larvae, pupae, moth, and egg) developing into a second generation. The second generation of PE-WC fed larvae of A. grisella efficiently degrades PE at par with first generation counterparts.


Assuntos
Mariposas/crescimento & desenvolvimento , Polietileno/análise , Resíduos/análise , Animais , Biodegradação Ambiental , Larva/crescimento & desenvolvimento , Larva/metabolismo , Estágios do Ciclo de Vida , Mariposas/metabolismo
19.
Ecotoxicol Environ Saf ; 180: 396-402, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31108416

RESUMO

Pb2+ pollution and poisoning are serious environmental and pharmacological concerns. The World Health Organization reported that Pb has resulted in 540,000 deaths in 2016 alone. Therefore, effective drugs or supplements that can alleviate or offset Pb2+-induced toxicity are badly needed. Through screening biocompatible natural compounds, we discovered that chicoric acid exhibited potent protective activities against Pb2+-induced toxicity both in BV-2 microglial cells and in zebrafish from the first days of development. Chicoric acid was able to reduce Pb2+-induced increases in levels of reactive oxygen species and tumor necrosis factor alpha, restoring the cell cycle in BV-2 cells. In the zebrafish model, chicoric acid significantly alleviated the Pb2+-induced serious mortality and malformation of zebrafish larvae in a concentration-dependent manner. These protective activities of chicoric acid were mainly from its alleviation of Pb2+-induced dysregulation of oxidative response pathways, including key genes such as Aox1, Gclm, Hmox1, Nqo1, Scd1, and Srxn1, as well as HO-1 protein. Since Pb2+ is difficult to be completely eliminated from the body and chelating agents may cause serious adverse effects, chicoric acid is likely a potential supplement therapy, in addition to current clinical practices.


Assuntos
Ácidos Cafeicos/farmacologia , Poluentes Ambientais/toxicidade , Larva/efeitos dos fármacos , Chumbo/toxicidade , Microglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Succinatos/farmacologia , Peixe-Zebra/metabolismo , Animais , Antioxidantes/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Larva/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
20.
Food Chem ; 292: 197-203, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054665

RESUMO

Future protein demand is expected to rise with global population growth. In this study a comprehensive sensorial analysis of the odor of honey bee (Apis mellifera) larvae and pupae as function of their diet (with and without added sugar solution) was performed, as well as nutritional values and antioxidant activity analysis. Honey bee brood powder is a potentially valuable nutritional source with 20-25% protein (dry matter basis), high antioxidant activity and polyphenol content. Main volatile compounds detected using GC-MS with HS-SPME injection were odorless pheromones that represented differences between larvae and pupae. The determined active odor compounds were 2- and 3-methylbutanal, diacetyl, nonanal, dimethyl sulfide and ocimene. A trained sensory panel described honey bee brood aroma profile mainly with buttery and milky attributes, with different life stages and diets giving similar profiles. Such studies can be useful for future development of food products with desired nutritional and sensorial characteristics.


Assuntos
Dieta , Odorantes/análise , Animais , Abelhas/crescimento & desenvolvimento , Depuradores de Radicais Livres/química , Cromatografia Gasosa-Espectrometria de Massas , Larva/química , Larva/metabolismo , Valor Nutritivo , Análise de Componente Principal , Pupa/química , Pupa/metabolismo , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação
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