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1.
Toxicol Lett ; 322: 131-139, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953209

RESUMO

Cyanotoxins, among which >200 variants of Microcystins (MC), constitute an emerging issue in food safety. Microcystins (MC) toxicity is congener-specific; however, the in vitro inhibition of PP1/PP2A (the key molecular event of MC toxicity) by single MC variants is comparable and MC toxicokinetics seems to be the critical point. Here, the variability in GSH conjugation catalysed by human recombinant enzymes and human hepatic cytosol has been compared between hydrophilic (MC-LR and MC-RR) and hydrophobic (MC-LW, MC-YR and MC-LF) variants, according to measured logPow. In vitro detoxication reaction (spontaneous plus enzymatic) is favored by the variant hydrophilicity, with MC-LF very poorly detoxified. With MC-YR and -LW the spontaneous reaction always gave the major contribution, whereas with MC-LR and -RR the enzymatic reaction became by far predominant when GSH was depleted. Consequently, the well-known GST polymorphisms seems not to be the major driver for potential human variability in susceptibility towards the MC-toxicity, except for MC-RR and -LR when GSH is depleted. Looking at these results and literature data, MC-RR (the least cytotoxic and acutely toxic in rodents) is the more hydrophilic, has the lowest OATP-mediated hepatic uptake and the highest detoxication efficiency. The opposite is true for the most lipophilic MC-LF: once entered in the cells with the highest uptake, it is very poorly detoxified, and resulted as the most toxic in various cell types. MC-dependent TK should be considered in order to estimate the variability in toxicity and to support the use of quantitative in vitro-in vivo extrapolation models of single toxins and their mixtures co-occurring in the environment.


Assuntos
Glutationa Transferase/metabolismo , Fígado/enzimologia , Microcistinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Glutationa/metabolismo , Glutationa Transferase/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Inativação Metabólica , Isoenzimas , Masculino , Microcistinas/química , Microcistinas/toxicidade , Estrutura Molecular , Polimorfismo Genético , Proteínas Recombinantes/metabolismo , Medição de Risco , Especificidade por Substrato , Toxicocinética
2.
Bull Entomol Res ; 110(1): 144-154, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31218990

RESUMO

We examined the role of the most important metabolic enzyme families in the detoxification of neurotoxic insecticides on adult males and females from susceptible populations of Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). The interaction between the enzyme families - carboxylesterases (EST), glutathione-S-transferases (GST), and polysubstrate monooxygenases (PSMO) - with the insecticides - chlorpyrifos, λ-cyhalothrin, and thiacloprid - was studied. Insect mortality arising from the insecticides, with the application of enzyme inhibitors - S,S,S-tributyl phosphorotrithioate (DEF), diethyl maleate (DEM), and piperonyl butoxide (PBO) - was first determined. The inhibitors' influence on EST, GST, and PSMO activity was quantified. EST and PSMO (the phase-I enzymatic activities) were involved in the insecticide detoxification in the three species for both sexes, highlighting the role of EST, whereas GST (phase-II enzymes) was involved only in G. molesta insecticide detoxification. L. botrana exhibited, in general, the highest level of enzymatic activity, with a significantly higher EST activity compared with the other species. It was the only species with differences in the response between sexes, with higher GST and PSMO activity in females than in males, which can be explained as the lower susceptibility of the females to the tested insecticides. A positive correlation between PSMO activity and the thiacloprid LD50s in the different species-sex groups was observed explaining the species-specific differences in susceptibility to the product reported in a previous study.


Assuntos
Inativação Metabólica , Inseticidas , Mariposas/enzimologia , Animais , Feminino , Masculino
3.
Bull Entomol Res ; 110(1): 57-67, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31217039

RESUMO

Glyphodes pyloalis Walker (Lepidoptera: Pyralididae) is a common pest in sericulture and has developed resistance to different insecticides. However, the mechanisms involved in insecticide resistance of G. pyloalis are poorly understood. Here, we present the first whole-transcriptome analysis of differential expression genes in insecticide-resistant and susceptible G. pyloalis. Clustering and enrichment analysis of DEGs revealed several biological pathways and enriched Gene Ontology terms were related to detoxification or insecticide resistance. Genes involved in insecticide metabolic processes, including cytochrome P450, glutathione S-transferases and carboxylesterase, were identified in the larval midgut of G. pyloalis. Among them, CYP324A19, CYP304F17, CYP6AW1, CYP6AB10, GSTs5, and AChE-like were significantly increased after propoxur treatment, while CYP324A19, CCE001c, and AChE-like were significantly induced by phoxim, suggesting that these genes were involved in insecticide metabolism. Furthermore, the sequence variation analysis identified 21 single nucleotide polymorphisms within CYP9A20, CYP6AB47, and CYP6AW1. Our findings reveal many candidate genes related to insecticide resistance of G. pyloalis. These results provide novel insights into insecticide resistance and facilitate the development of insecticides with greater specificity to G. pyloalis.


Assuntos
Inativação Metabólica/genética , Resistência a Inseticidas/genética , Mariposas/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/genética , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Masculino , Mariposas/genética , Polimorfismo de Nucleotídeo Único , Transcriptoma
4.
Chemosphere ; 240: 124914, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31557642

RESUMO

Arsenic (As) contamination is one of the most daunting environmental problem bothering the whole world. Exploring a suitable bioremediation technique is an urgent need of the hour. The present study focusses on scrutinizing the ectomycorrhizal (ECM) fungus for its potential role in As detoxification and understanding the molecular mechanisms responsible for its tolerance. When exposed to increasing concentrations of external As, the ECM fungus H. cylindrosporum accumulated the metalloid intracellularly, inducing the glutathione biosynthesis pathway. The genes coding for GSH biosynthesis enzymes, γ-glutamylcysteine synthetase (Hcγ-GCS) and glutathione synthetase (HcGS) were highly regulated by As stress. Arsenic coordinately upregulated the expression of both Hcγ-GCS and HcGS genes, thus resulting in increased Hcγ-GCS and HcGS protein expressions and enzyme activities, with substantial increase in intracellular GSH. Functional complementation of the two genes (Hcγ-GCS and HcGS) in their respective yeast mutants (gsh1Δ and gsh2Δ) further validated the role of both enzymes in mitigating As toxicity. These findings clearly highlight the potential importance of GSH antioxidant defense system in regulating the As induced responses and its detoxification in ECM fungus H. cylindrosporum.


Assuntos
Arsênico/toxicidade , Glutationa/biossíntese , Hebeloma/efeitos dos fármacos , Micorrizas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Arsênico/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Teste de Complementação Genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Hebeloma/genética , Hebeloma/metabolismo , Inativação Metabólica , Mutação , Micorrizas/genética , Micorrizas/metabolismo , Saccharomyces cerevisiae/metabolismo , Poluentes do Solo/metabolismo
5.
Chemosphere ; 240: 124949, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568949

RESUMO

Pharmaceutically active compounds are of great concern due to their detection frequency in the environment and the unexpected risks. In this study, the simultaneous removal of mixed pharmaceuticals by microalgae was explored using a typical freshwater diatom Navicula sp. Results showed that Navicula sp. could efficiently remove atenolol, carbamazepine, ibuprofen and naproxen with the efficiencies of >90% after 21 d of exposure. As compared to the removal efficiencies of each pharmaceutical in the individual pharmaceutical treatments, the degradation of sulfamethoxazole, bezafibrate, and naproxen was improved in the mixed treatment, whereas the removal efficiencies of carbamazepine and atenolol decreased. Additionally, the presence of hydrophobic pharmaceuticals (i.e., ibuprofen and naproxen) accelerated the degradation of carbamazepine and sulfamethoxazole and inhibited the removal of atenolol in the mixture with the combination of six pharmaceuticals, while the addition of other pharmaceuticals show no significant effect on the removal of ibuprofen and naproxen. The bioaccumulation of pharmaceuticals in Navicula sp. increased as their log KOW values decreased. Four bezafibrate metabolites were identified and the degradation pathways of bezafibrate in diatom were proposed. It is the first report on the metabolism of BEZ in diatom, and further studies on the environmental risk of the metabolites should be investigated.


Assuntos
Bezafibrato/análise , Biodegradação Ambiental , Diatomáceas/metabolismo , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/metabolismo , Poluentes Químicos da Água/análise , Atenolol/análise , Carbamazepina/análise , Água Doce/química , Ibuprofeno/análise , Inativação Metabólica , Naproxeno/análise , Sulfametoxazol/análise
6.
Rev Environ Contam Toxicol ; 252: 1-50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31451946

RESUMO

Microbe-assisted organopollutant removal, or in planta crop decontamination, is based on an interactive system between organopollutant-degrading endophytic bacteria (DEBOP) and crops in alleviating organic toxins in plants. This script focuses on the fast-growing body of literature that has recently bloomed in organopollutant control in agricultural plants. The various facets of DEBOP under study include their colonization, distribution, plant growth-promoting mechanisms, and modes of action in the detoxification process in plants. Also, an assessment of the biotechnological advances, advantages, and bottlenecks in accelerating the implementation of this decontamination strategy will be undertaken. The highlighted key research directions from this review will shape the future of agro-environmental sustainability and preservation of human health.


Assuntos
Bactérias , Produtos Agrícolas/microbiologia , Endófitos , Poluentes do Solo/metabolismo , Agricultura , Produtos Agrícolas/metabolismo , Inativação Metabólica , Desenvolvimento Vegetal
7.
Ceska Slov Farm ; 68(4): 139-147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31822106

RESUMO

Benzodiazepines (BZDs) and Z-drugs are strongly addictive substances, acting on identical GABA receptors. Detoxification should be long-term and gradual, usually by tapering a long-acting BZD (diazepam) but no suitable commercial pharmaceutic product exists with the necessary low drug content. This review describes the specific pharmacological aspects and comparisons of individual BZDs in relation to their effects and addictiveness. The success of the treatment relates to the patients comfort during this process. Patients are typically afraid of switching to a more suitable long-acting BZD (diazepam), and become stressed during the tapering and anxious from withdrawal symptoms. These obstacles could be overcome through individualized detoxification according to already published withdrawal schedules based on the administration of very precise diazepam doses in a long-term gradual tapering with possible addition of adjuvant drugs. Dose reduction does not change external appearance of the dosage form, and the patient could be treated until the placebo phase. Individually prepared pharmaceutics with different and precise diazepam contents can be used for comfortable detoxification and also may eliminate psychogenic stress during switching, tapering, and the withdrawal period.


Assuntos
Benzodiazepinas/efeitos adversos , Diazepam/uso terapêutico , Síndrome de Abstinência a Substâncias/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Benzodiazepinas/administração & dosagem , Esquema de Medicação , Humanos , Inativação Metabólica
8.
Int J Nanomedicine ; 14: 6917-6932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695366

RESUMO

Aim: To determine whether the use of a mixed polymeric micelle delivery system based on vitamin E succinate (VES)-grafted-chitosan oligosaccharide (CSO)/VES-grafted-chitosan (CS) mixed micelles (VES-g-CSO/VES-g-CS MM) enhances the delivery of C-DMSA, a theranostic fluorescent probe, for Hg2+ detection and detoxification in vitro and in vivo. Methods: Mixed micelles self-assembled from two polymers, VES-g-CSO and VES-g-CS, were used to load C-DMSA and afforded C-DMSA@VES-g-CSO/VES-g-CS MM for cell and in vivo applications. Fluorescence microscopy was used to assess C-DMSA cellular uptake and Hg2+ detection in L929 cells. C-DMSA@VES-g-CSO/VES-g-CS MM was then administered intravenously. Hg2+ detection was assessed by fluorescence microscopy in terms of bio-distribution while detoxification efficacy in Hg2+-poisoned rat models was evaluated in terms of mercury contents in blood and in liver. Results: The C-DMSA loaded mixed micelles, C-DMSA@VES-g-CSO/VES-g-CS MM, significantly enhanced cellular uptake and detoxification efficacy of C-DMSA in Hg2+ pretreated human L929 cells. Evidence from the reduction of liver coefficient, mercury contents in liver and blood, alanine transaminase and aspartate transaminase activities in Hg2+ poisoned SD rats treated with the mixed micelles strongly supported that the micelles were effective for Hg2+ detoxification in vivo. Furthermore, ex vivo fluorescence imaging experiments also supported enhanced Hg2+ detection in rat liver. Conclusion: The mixed polymeric micelle delivery system could significantly enhance cell uptake and efficacy of a theranostic probe for Hg2+ detection and detoxification treatment in vitro and in vivo. Moreover, this nanoparticle drug delivery system could achieve targeted detection and detoxification in liver.


Assuntos
Quitosana/química , Fígado/metabolismo , Mercúrio/análise , Micelas , Oligossacarídeos/química , Succímero/química , alfa-Tocoferol/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Morte Celular/efeitos dos fármacos , Linhagem Celular , Quitosana/síntese química , Liberação Controlada de Fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Inativação Metabólica/efeitos dos fármacos , Masculino , Mercúrio/sangue , Camundongos Endogâmicos BALB C , Nanopartículas/química , Oligossacarídeos/síntese química , Ratos Sprague-Dawley , Succímero/síntese química , alfa-Tocoferol/síntese química , alfa-Tocoferol/química
9.
Insect Biochem Mol Biol ; 115: 103247, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31626952

RESUMO

The diamondback moth, Plutella xylostella, is a damaging pest of cruciferous crops, and has evolved resistance to many of the insecticides used for control, including members of the diamide class. Previous work on the molecular basis of resistance to diamides has documented mutations in the target-site, the ryanodine receptor, in resistant populations of P. xylostella worldwide. In contrast the role of metabolic resistance to this insecticide class is significantly less clear. Here we show that overexpression of a flavin-dependent monooxgenase (FMO) confers resistance to the diamide chlorantraniliprole in P. xylostella. Transcriptome profiling of diamide resistant strains, with and without target-site resistance, revealed constitutive over-expression of several transcripts encoding detoxification enzymes compared to susceptible strains. Two of these, CYP6BG1, and PxFMO2 were particularly highly overexpressed (33,000 and 14,700-fold, respectively) in a resistant strain (HAW) lacking target-site resistance. After 17 generations without diamide selection the resistance of the HAW strain fell by 52-fold and the expression of PxFMO2 by > 1300-fold, however, the expression of CYP6BG1 declined by only 3-fold. Generation of transgenic Drosophila melanogaster expressing these genes demonstrated that PxFMO2, but not CYP6BG1, confers resistance in vivo. Overexpression of PxFMO2 in the HAW strain is associated with mutations, including a putative transposable element insertion, in the promoter of this gene. These enhance the expression of a reporter gene when expressed in a lepidopteran cell line suggesting they are, at least in part, responsible for the overexpression of PxFMO2 in the resistant strain. Our results provide new evidence that insect FMOs can be recruited to provide resistance to synthetic insecticides.


Assuntos
Família 6 do Citocromo P450/metabolismo , Inseticidas , Mariposas/enzimologia , Oxigenases/metabolismo , ortoaminobenzoatos , Animais , Feminino , Perfilação da Expressão Gênica , Inativação Metabólica , Resistência a Inseticidas , Masculino
10.
Environ Pollut ; 255(Pt 2): 113329, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31600704

RESUMO

Transcription factors including pregnane X receptor (Pxr) and nuclear factor-erythroid 2-related factor-2 (Nrf2) are important modulators of Adenosine triphosphate-binding cassette (ABC) transporters in mammalian cells. However, whether such modulation is conserved in zebrafish embryos remains largely unknown. In this manuscript, pxr- and nrf2-deficient models were constructed with CRISPR/Cas9 system, to evaluate the individual function of Pxr and Nrf2 in the regulation of ABC transporters and detoxification of heavy metal ions like Cd2+ and Ag+. As a result, both Cd2+ and Ag+ conferred extensive interactions with ABC transporters in wild type (WT) embryos: their accumulation and toxicity were affected by the activity of ABC transporters, and they significantly induced the mRNA expressions of ABC transporters. These induction effects were reduced by the mutation of pxr and nrf2, but elevations in the basal expression of ABC transporters compensated for the loss of their inducibility. This could be an explanation for remaining transporter function in both mutant models as well as the unaltered toxicity of metal ions in pxr-deficient embryos. However, mutation of nrf2 disrupted the production of glutathione (GSH), resulting in the enhanced toxicity of Cd2+/Ag+ in zebrafish embryos. In addition, elevated expressions of other transcription factors like aryl hydrocarbon receptor (ahr) 1b, peroxisome proliferator-activated receptor (ppar)-ß, and nrf2 were found in pxr-deficient models without any treatment, while enhanced induction of ahr1b, ppar-ß and pxr could only be seen in nrf2-deficient embryos after the treatment of metal ions, indicating different compensation phenomena for the absence of transcription factors. After all, pxr-deficient and nrf2-deficient zebrafish embryos are useful tools in the functional investigation of Pxr and Nrf2 in the early life stages of aquatic organisms. However, the compensatory mechanisms should be taken into consideration when interpreting the results and need in-depth investigations.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Metais Pesados/toxicidade , Fator 2 Relacionado a NF-E2/genética , Receptor de Pregnano X/genética , Peixe-Zebra/embriologia , Animais , Glutationa/metabolismo , Inativação Metabólica , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Esteroides/genética , Fatores de Transcrição/metabolismo , Proteínas de Peixe-Zebra/metabolismo
11.
Ecotoxicol Environ Saf ; 185: 109692, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585391

RESUMO

Canna indica L. is a promising species for heavy metal phytoremediation due to its fast growth rate and large biomass. However, few studies have investigated cadmium (Cd) tolerance mechanisms. In the present study, Canna plants were cultivated under hydroponic conditions with increasing Cd concentrations (0, 5, 10, 15 mg/L). We found that the plants performed well under 5 mg/L Cd2+ stress, but damage was observed under higher Cd exposure, such as leaf chlorosis, growth inhibition, a decreased chlorophyll content, and destruction of the ultrastructure of leaf cells. Additionally, Canna alleviated Cd toxicity to a certain extent. After Canna was exposed to 5, 10 and 15 mg/L Cd2+ for 45 d, the highest Cd concentration was exhibited in roots, which was almost 17-47 times the Cd concentration in leaves and 8-20 times that in stems. At the subcellular level, cellular debris and heat-stable proteins (HSPs) were the main binding sites for Cd, and the proportion of Cd in the two subcellular fractions accounted for 71.4-94.2% of the total Cd. Furthermore, we found that granules could participate in the detoxification process when Cd stress was enhanced. Our results indicated that Canna indica L. can tolerate Cd toxicity by sequestering heavy metals in root tissues, fencing out by cell wall, and binding with biologically detoxified fractions (granules and HSPs).


Assuntos
Cádmio/toxicidade , Poluentes do Solo/toxicidade , Frações Subcelulares/efeitos dos fármacos , Zingiberales/efeitos dos fármacos , Biodegradação Ambiental , Biomassa , Cádmio/metabolismo , Relação Dose-Resposta à Radiação , Tolerância a Medicamentos , Inativação Metabólica , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Poluentes do Solo/metabolismo , Frações Subcelulares/metabolismo , Frações Subcelulares/ultraestrutura , Zingiberales/metabolismo , Zingiberales/ultraestrutura
12.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606747

RESUMO

Glutathione conjugation is a crucial step in xenobiotic detoxification. In the current study, we have functionally characterized an epsilon-class glutathione S-transferase (GST) from a brown planthopper Nilaparvata lugens (nlGSTE). The amino acid sequence of nlGSTE revealed approximately 36-44% identity with epsilon-class GSTs of other species. The recombinant nlGSTE was prepared in soluble form by bacterial expression and was purified to homogeneity. Mutation experiments revealed that the putative substrate-binding sites, including Phe107, Arg112, Phe118, and Phe119, were important for glutathione transferase activity. Furthermore, inhibition study displayed that nlGSTE activity was affected by insecticides, proposing that, in brown planthopper, nlGSTE could recognize insecticides as substrates.


Assuntos
Glutationa Transferase/metabolismo , Hemípteros/enzimologia , Sequência de Aminoácidos , Animais , Escherichia coli , Glutationa Transferase/química , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/genética , Hemípteros/genética , Inativação Metabólica , Inseticidas/farmacologia , Mutagênese Sítio-Dirigida
13.
Adv Exp Med Biol ; 1141: 341-360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571169

RESUMO

The kidney plays an important role in maintaining total body homeostasis and eliminating toxic xenobiotics and metabolites. Numerous drugs and their metabolites are ultimately eliminated in the urine. The reabsorption and secretion functions of the nephron are mediated by a variety of transporters located in the basolateral and luminal membranes of the tubular cells. In the past decade, many studies indicated that transporters play important roles in drug pharmacokinetics and demonstrated the impact of renal transporters on the disposition of drugs, drug-drug interactions, and nephrotoxicities. Here, we focus on several important renal transporters and their roles in drug elimination and disposition, drug-induced nephrotoxicities and potential clinical solutions.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Rim , Proteínas de Membrana Transportadoras , Preparações Farmacêuticas , Animais , Transporte Biológico , Interações de Medicamentos , Humanos , Inativação Metabólica , Rim/efeitos dos fármacos , Preparações Farmacêuticas/metabolismo
14.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639190

RESUMO

Plants present a delimited reservoir of biologically active compounds. Many plants synthesize several compounds of secondary metabolism, such as alkaloids, terpenoids, phenolics, steroids, etc. Such compounds are generally thought to be involved in plant-insect interactions. Phytoecdysteroids are a class of chemicals that plants synthesize; these compounds are analogues of molting hormones produced by insects. In this work, the effect of the 20-hydroxyecdysone, which is a molecule that belongs to the family of phytoecdysteroids, was tested on an insect pest, Tribolium castaneum (Herbst). Firstly, the effect of this molecule on post-embryonic development parameters was tested after ingestion at 300, 600, 900, and 1,200 ppm. Secondly, the effect of the 20-hydroxyecdysone was also tested on the biological parameters (proteins, alpha-amylase, detoxification enzymes). The results of the post-embryonic parameters test showed an important induction of larval mortality and a significant reduction of pupation and adult emergence rates. On the other hand, the test on the biological parameters showed that the 20-hydroxyecdysone caused a significant decrease in the levels of soluble proteins in treated larvae. In addition, the alpha-amylase activity was significantly inhibited by the ingestion of the phytoecdysteroid. And there was also a disruption of detoxification enzymes. The whole of the disturbances recorded in this work prove that phytoecdysteroids are thought to have potential value on T. castaneum control.


Assuntos
Ecdisterona/farmacologia , Inativação Metabólica/efeitos dos fármacos , Inseticidas/farmacologia , Tribolium/efeitos dos fármacos , Animais , Digestão/fisiologia , Sistema Digestório/enzimologia , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/crescimento & desenvolvimento , Tribolium/enzimologia , Tribolium/crescimento & desenvolvimento
15.
Ecotoxicol Environ Saf ; 185: 109735, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586846

RESUMO

Nilaparvata lugens(Stål) is a serious pest of rice and has evolved different levels of resistance against most chemical pesticides. ß-asarone is the main bioactive insecticidal compound of Acorus calamus L. that shows strong insecticidal activity against pests. In this study, we conducted a bioassay experiment to determine the contact toxicity of ß-asarone to N. lugens nymphs. The LD30 sublethal dose was 0.106 µg per nymph, with 95% confidence limits of 0.070-0.140 µg. We applied the LD30 concentration of ß-asarone to nymphs for 24 h or 72 h and then performed a transcriptome sequence analysis by referencing the N. lugens genome to characterize the variation. The transcriptomic analysis showed that several GO terms and KEGG pathways presented significant changes. Individually, 126 differentially expressed genes (DEGs), including 72 upregulated and 54 downregulated genes, were identified at 24 h, and 1771 DEGs, including 882 upregulated and 889 downregulated genes, were identified at 72 h. From the DEGs, we identified a total of 40 detoxification-related genes, including eighteen Cytochrome P450 monooxygenase genes (P450s), three Glutathione S-transferase genes, one Carboxylesterase gene, twelve UDP-glucosyltransferases and six ATP-binding cassette genes. We selected the eighteen P450s for subsequent verification by quantitative PCR. These findings indicated that ß-asarone presented strong contact toxicity to N. lugens nymphs and induced obvious variation of detoxification-related genes that may be involved in the response to ß-asarone.


Assuntos
Anisóis/farmacologia , Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Ninfa/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Carboxilesterase/genética , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Genoma , Glutationa Transferase/genética , Hemípteros/genética , Hemípteros/metabolismo , Inativação Metabólica/genética , Ninfa/genética , Ninfa/metabolismo , Oryza/crescimento & desenvolvimento
16.
Ecotoxicol Environ Saf ; 185: 109698, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31574370

RESUMO

Salt-tolerant rice cultivar (sea rice) is a research hotspot worldwide due to its high yield in high salinity soil. However, knowledge regarding the cadmium (Cd) effects on the growth of sea rice is limited. To determine the short-term and long-term impact of Cd stress, relatively low/high Cd-accumulative rice cultivars and sea rice were grown to compare their growth responses to Cd stress over time. The results showed that sea rice presented the highest Cd concentrations in the root, stem, and leaves under 32-days of Cd stress. Cd stress shortened and thickened the rice root, and decreased the proportion of root diameters in the 0-0.2 mm range. Cd stress remarkably increased the Cd and Fe concentration in dithionite-citrate-bicarbonate (DCB) extracts, and the DCB-Cd and DCB-Fe concentrations were the highest in sea rice. The subcellular distribution of Cd in the rice roots indicated that Cd accumulated the most in the soluble fraction and cell wall. The contents of pectin and hemicellulose 2 in the root cell wall of the low-Cd accumulative rice variety CL755 were higher than those in MXZ and sea rice. Collectively, this work provides a general understanding of the Cd effects on sea rice growth and indicates that sea rice has a relatively high Cd accumulation compared with the other two rice cultivars. However, the specifically-related mechanism remains to be further studied.


Assuntos
Cádmio/metabolismo , Espaço Intracelular/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Parede Celular/metabolismo , Inativação Metabólica , Oryza/crescimento & desenvolvimento , Pectinas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Polissacarídeos/metabolismo , Solo/química
17.
Chemosphere ; 235: 1097-1106, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561300

RESUMO

Neonicotinoid insecticides show high persistence in the environment, and standard biological approaches such as biopurification systems have shown mostly inefficient removal of such compounds. In this work, soil pre-exposed to imidacloprid was used to obtain presumptive imidacloprid-degrading consortia. Cometabolic enrichment yielded a microbial consortium composed of eight bacterial and one yeast strains, capable of degrading not only this compound, but also thiamethoxam and acetamiprid, as demonstrated in cross-degradation assays. The biological removal process was scaled-up to batch stirred tank bioreactors (STBR); this configuration was able to simultaneously remove mixtures of imidacloprid + thiamethoxam or imidacloprid + thiamethoxam + acetamiprid, reaching elimination of 95.8% and 94.4% of total neonicotinoids, respectively. Removal rates in the bioreactors followed the pattern imidacloprid > acetamiprid > thiamethoxam, including >99% elimination of imidacloprid in 6 d and 17 d (binary and ternary mixtures, respectively). A comprehensive evaluation of the detoxification in the STBR was performed using different biomarkers: seed germination (Lactuca sativa), bioluminescence inhibition (Vibrio fischeri), and acute oral tests in honeybees. Overall, ecotoxicological tests revealed partial detoxification of the matrix, with clearer detoxification patterns in the binary mixture. This biological approach represents a promising option for the removal of neonicotinoids from agricultural wastewater; however, optimization of the process should be performed before application in farms.


Assuntos
Inseticidas/isolamento & purificação , Consórcios Microbianos , Neonicotinoides/isolamento & purificação , Purificação da Água/métodos , Agricultura , Animais , Abelhas , Ecotoxicologia/métodos , Inativação Metabólica , Inseticidas/análise , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Águas Residuárias/química
18.
Chemosphere ; 237: 124468, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549634

RESUMO

In order to assess the toxicity of Cypermethrin (CYP), the 50% lethal concentration (LC50) of CYP on the juvenile of Cherax quadricarinatus is assessed. Meanwhile, the transcription level and the content in the antioxidant and biotransformation enzymes in hepatopancreas and immune enzymes in the serum of C. quadricarinatus exposed to CYP (0.1, 1, 10 and 100 ng·L-1) for 96 h were analyzed to reveal the CYP toxicity and detoxification mechanism. 24, 48, 72, 96 h LC50 were 1305.14, 424.52, 287.10 and 215.99 ng·L-1, respectively. There was no significant change of the content of enzymes at low concentration (0.16 ng·L-1). The fast increase of SOD and CAT content was observed at early stage (24 h), subsequent decreased at later stage of trail at medium concentration (0.32 and 0.63 ng·L-1). However, high concentration (1.25 ng·L-1) of CYP significantly inhibited SOD and CAT content. There was a significant increase in the level of MDA, PC and the content of GPx, EROD, CarE, GST at medium and high concentration after 72 h and 96 h exposure. The Na+-K+-ATPase, PO, ALK content decreased at medium and high concentration, especially at the 72-h and the 96-h exposure. The transcription was altered similarly to enzyme content, but the transcriptional response was generally more immediate than enzymatic response. Heat shock protein (hsp70) and multidrug resistance-associated protein 2 (abcc2) genes were up-regulated.


Assuntos
Astacoidea/fisiologia , Piretrinas/toxicidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes , Astacoidea/enzimologia , Biotransformação , Hepatopâncreas/enzimologia , Inativação Metabólica
19.
BMC Complement Altern Med ; 19(1): 237, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481128

RESUMO

BACKGROUND: Rice husk, a waste material produced during milling, contains numerous phytochemicals that may be sources of cancer chemopreventive agents. Various biological activities of white and colored rice husk have been reported. However, there are few comparative studies of the cancer chemopreventive effects of white and colored rice husk. METHODS: This study investigated the cancer chemopreventive activities of two different colors of rice husk using in vitro and in vivo models. A bacterial mutation assay using Salmonella typhimurium strains TA98 and TA100 was performed; enzyme induction activity in murine hepatoma cells was measured, and a liver micronucleus test was performed in male Wistar rats. RESULTS: The white rice husk (WRHE) and purple rice husk (PRHE) extracts were not mutagenic in Salmonella typhimurium TA98 or TA100 in the presence or absence of metabolic activation. However, the extracts exhibited antimutagenicity against aflatoxin B1 (AFB1) and 2-amino-3,4 dimethylimidazo[4,5-f]quinolone (MeIQ) in a Salmonella mutation assay. The extracts also induced anticarcinogenic enzyme activity in a murine Hepa1c1c7 hepatoma cell line. Interestingly, PRHE but not WRHE exhibited antigenotoxicity in the rat liver micronucleus test. PRHE significantly decreased the number of micronucleated hepatocytes in AFB1-initiated rats. PRHE contained higher amounts of phenolic compounds and vitamin E than WRHE in both tocopherols and tocotrienols as well as polyphenol such as cyanidin-3-glucoside, protocatechuic acid and vanillic acid. Furthermore, PRHE increased CYP1A1 and 1A2 activities while decreasing CYP3A2 activity in the livers of AFB1-treated rats. PRHE also enhanced various detoxifying enzyme activities, including glutathione S-transferase, NAD(P)H quinone oxidoreductase and heme oxygenase. CONCLUSIONS: PRHE showed potent cancer chemopreventive activity in a rat liver micronucleus assay through modulation of phase I and II xenobiotic metabolizing enzymes involved in AFB1 metabolism. Vitamin E and phenolic compounds may be candidate antimutagens in purple rice husk.


Assuntos
Aflatoxina B1/toxicidade , Inativação Metabólica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Oryza/química , Animais , Antimutagênicos/farmacologia , Linhagem Celular , Fígado/citologia , Fígado/enzimologia , Fígado/metabolismo , Masculino , Testes para Micronúcleos , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Salmonella typhimurium/efeitos dos fármacos
20.
BMC Infect Dis ; 19(1): 704, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399061

RESUMO

BACKGROUND: Plasmodium vivax transmission in West Africa, dominant for the Duffy-negative blood group, has been increasingly recognized from both local residents as well as international travelers who contracted P. vivax malaria there. However, the relapsing pattern and sensitivity to antimalarial treatment of P. vivax strains originated from this region are largely unknown. There is evidence that the efficacy of primaquine for radical cure of relapsing malaria depends on host factors such as the hepatic enzyme cytochrome P450 (CYP) 2D6. CASE PRESENTATION: A 49-year-old Chinese man was admitted to the Shanglin County Hospital in Guangxi Province, China, on December 19, 2016, 39 days after he returned from Ghana, where he stayed for one and a half years. He was diagnosed by microscopy as having uncomplicated P. vivax malaria. Treatment included 3 days of intravenous artesunate (420 mg total), and 3 days of chloroquine (1550 mg total), and 8 days of primaquine (180 mg total). Although parasites and symptoms were cleared rapidly and he was malaria-negative for almost two months, he suffered four relapses with relapse intervals ranging from 58 to 232 days. The last relapse occurred at 491 days from his first vivax attack. For the first three relapses, he was treated similarly with chloroquine and primaquine, sometimes supplemented with additional artemisinin combination therapies (ACTs). For the last relapse, he was treated with intravenous artesunate, 3 days of an ACT, and 7 days of azithromycin, and had remained healthy for 330 days. Molecular studies confirmed P. vivax infections for all the episodes. Although this patient was diagnosed to have normal glucose-6-phosphate dehydrogenase (G6PD) activity, his CYP2D6 genotype corresponded to a *2A/*36 allele variant suggesting of an impaired primaquine metabolizer phenotype. CONCLUSIONS: This clinical case suggests that P. vivax malaria originating from West Africa may produce multiple relapses extending beyond one year. The failures of primaquine as an anti-relapse therapy may be attributed to the patient's impaired metabolizer phenotype of the CYP2D6. This highlights the importance of knowing the host G6PD and CYP2D6 activities for effective radical cure of relapsing malaria by primaquine.


Assuntos
Citocromo P-450 CYP2D6/metabolismo , Malária Vivax/tratamento farmacológico , Malária Vivax/parasitologia , Plasmodium vivax/patogenicidade , Antimaláricos/farmacocinética , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato/uso terapêutico , Cloroquina/uso terapêutico , Citocromo P-450 CYP2D6/genética , Gana , Humanos , Inativação Metabólica , Masculino , Pessoa de Meia-Idade , Plasmodium vivax/genética , Primaquina/farmacocinética , Primaquina/uso terapêutico , Recidiva
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