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1.
Pest Manag Sci ; 75(11): 2916-2924, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465149

RESUMO

BACKGROUND: The aryl hydrocarbon receptor (AhR) belongs to the bHLH-PAS (basic Helix-Loop-Helix - Period/ARNT/Single minded) family of transcription factors. AhR is a ligand-activated transcription factor, which participates in the sensing and transmitting stimuli of endogenous and exogenous chemicals, and subsequently activates the transcription of genes related to various physiological and detoxification functions. RESULT: In this study, a single full-length LmAhR sequence was cloned and characterized. RNA interference (RNAi) and insecticide bioassays showed that LmAhR plays a vital role in chlorpyrifos susceptibility. To better identify aryl hydrocarbon receptor from locusta migratoria (LmAhR)-regulated genes involved in chlorpyrifos susceptibility, a comparative transcriptome analysis was performed using double-stranded (ds)GFP- and dsLmAhR-injected Locusta migratoria. Differential gene expression analysis identified 145 down-regulated and 67 up-regulated genes (P ≤ 0.05 and fold change ≥2) in dsLmAhR-knockdown insects. We selected 27 down-regulated genes and verified their expression levels using reverse transcription quantitative PCR. Finally, one glutathione S-transferase (GST) gene (LmGSTd7) was selected as a candidate detoxification gene and was further validated via RNAi and chlorpyrifos bioassays. CONCLUSION: Our data suggest that AhR is associated with chlorpyrifos susceptibility via the regulation of LmGSTd7 expression in L. migratoria. © 2019 Society of Chemical Industry.


Assuntos
Clorpirifos/farmacologia , Regulação da Expressão Gênica , Glutationa Transferase/genética , Gafanhotos/efeitos dos fármacos , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Receptores de Hidrocarboneto Arílico/genética , Animais , Glutationa Transferase/metabolismo , Gafanhotos/genética , Gafanhotos/crescimento & desenvolvimento , Proteínas de Insetos/metabolismo , Ninfa/efeitos dos fármacos , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Receptores de Hidrocarboneto Arílico/metabolismo
2.
Chemosphere ; 227: 425-434, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31003127

RESUMO

Pesticide pollution residues have become increasingly common health hazards over the last several decades because of the wide use of pesticides. The gastrointestinal tract is the first physical and biological barrier to contaminated food and is therefore the first exposure site. Interestingly, a number of studies have shown that the gut microbiota plays a key role in the toxicity of pesticides and has a profound relationship with environmental animal and human health. For instance, intake of the pesticide of chlorpyrifos can promote obesity and insulin resistance through influencing gut and gut microbiota of mice. In this review, we discussed the possible effects of different kinds of widely used pesticides on the gut microbiota in different experimental models and analyzed their possible subsequent effects on the health of the host. More and more studies indicated that the gut microbiota of animals played a very important role in pesticides-induced toxicity, suggesting that gut micriobita was also the unintended recipient of pesticides. We hope that more attention can focus on the relationship between pesticides, gut microbiota and environmental health risk assessment in near future.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Praguicidas/toxicidade , Animais , Clorpirifos/farmacologia , Poluição Ambiental , Trato Gastrointestinal , Humanos , Obesidade
3.
Biomed Pharmacother ; 114: 108795, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30909143

RESUMO

Pesticides, such as organophosphorus and pyrethroids, are extensively used in the agrofields which can significantly increase crop productivity. Humans are exposed to pesticides via dermal contact, inhalation and ingestion due to occupational exposure. The objective of the present study was to evaluate the protective role of the aqueous extract of Crataegus oxyacantha during acute exposure of rats to the combination of deltamethrin (DM) and chlorpyrifos (CPF) in rats (DCF). The combination of vitamins C and E (Vit CE) was used as a standard antioxidant. The Crataegus oxyacantha extract revealed the presence of a high level of phenolic compounds identified by HPLC analysis. Male wistar rats were divided into six groups: (I) corn oil, (II) AECO (1 ml/100 g), (III) DCF (DM 5 mg/kg, CPF 1 mg/kg), (IV) AECO + DCF, (V) Vit CE (Vit C 100 mg/kg, Vit E 100 mg/kg), and (VI) Vit CE + DCF. AECO and Vit CE were administered 10 days before the administration of DCF. The findings revealed that the administration of DM and CPF mixture induced a significant decrease in serum AChE and DNA damage, as indicated by brain DNA fragmentation. In addition, behavioral tests by open field and elevated plus maze showed impaired recognition memory. The results showed that AECO or Vit CE alleviated significantly neurobehavioral alterations, reduced lipid peroxidation in brain, and restored the antioxidant parameters (SOD, CAT, GPx and GSH) to normal levels. Furthermore, brain DNA fragmentation and histopathology in DCF treated rats were improved by AECO administration. All results revealed that C. oxyacantha extract, rich in polyphenolic compounds, had potential antioxidant effects on the combination of DM and CPF-induced oxidative brain damage.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Clorpirifos/farmacologia , Crataegus/química , Inseticidas/farmacologia , Nitrilos/farmacologia , Extratos Vegetais/farmacologia , Piretrinas/farmacologia , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Encéfalo/metabolismo , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/farmacologia , Ratos , Ratos Wistar , Vitamina E/farmacologia
4.
Oxid Med Cell Longev ; 2019: 1763589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881588

RESUMO

Neutrophil extracellular traps (NETs) are reticular structures formed by myeloperoxidase (MPO), histones, and neutrophil elastase (NE) that are released from neutrophils in response to pathogenic stimuli. Chlorpyrifos (CPF) is wildly used as an organophosphorus pesticide that causes a range of toxicological and environmental problems. Exposure to CPF can increase the production of neutrophils in carps, and this increase can be considered a biomarker of water pollution. To explore a relationship between NETs and CPF and its mechanism of influence, we treated neutrophils from the blood of carp with 1 µg/mL phorbol 12-myristate 13-acetate (PMA), 0.325 mg/L CPF, or 20 µM necrostatin-1 (Nec-1). The production of MPO and NETs was reduced in the CPF+PMA group compared with that in the PMA group. CPF can cause an increase in reactive oxygen species (ROS), while inhibiting respiratory burst caused by PMA stimulation. We found that the expression levels of protein-coupled receptor 84 (gpr84), dystroglycan (DAG), proto-oncogene serine/threonine kinase (RAF), protein kinase C (PKC), and mitogen-activated protein kinase 3 (MAPK3) in the CPF+PMA group were lower than those in the PMA group, indicating that the PKC-MAPK pathway was suppressed. The expression levels of cylindromatosis (CYLD), mixed lineage kinase domain-like pseudokinase (MLKL), receptor-interacting serine-threonine kinase 1 (RIP1), and receptor-interacting serine-threonine kinase 3 (RIP3) were increased, and the expression levels of caspase 8 were reduced by CPF, indicating that CPF may cause necroptosis. The addition of Nec-1 restored the number of NETs in the CPF+PMA group. The results indicate that CPF reduced the production of NETs by inhibiting respiratory burst and increasing necroptosis. The results contribute to the understanding of the immunotoxicological mechanism of CPF and provide a reference for comparative medical studies.


Assuntos
Clorpirifos/efeitos adversos , Inibidores da Colinesterase/efeitos adversos , Armadilhas Extracelulares/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/metabolismo , Proteína Quinase C/metabolismo , Explosão Respiratória/genética , Animais , Apoptose , Clorpirifos/farmacologia , Inibidores da Colinesterase/farmacologia , Peixes , Humanos , Necrose
5.
Chemosphere ; 225: 126-134, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30870629

RESUMO

Metals and organophosphorous pesticides commonly co-occur in marine environment, but the effect of their mixtures on non-target organisms is still poorly understood. This study investigated the combined effect of the essential metal copper (Cu) and organophosphorous pesticide chlorpyrifos (Chp) in mussels (Mytilus galloprovincialis) after short-term exposure to their sublethal concentrations. Mussels were exposed for four days to 5 and 15 µg L-1 Cu and 0.05 and 5 µg L-1 Chp, and to their binary mixtures. The investigated biomarkers, namely acetylcholinesterase activity (AChE), glutathione S-transferase activity (GST), metallothioneins content (MTs) and lipid peroxide levels (LPO) displayed unspecific and inconsistent response patterns that varied depending on the concentration of chemicals and composition of mixtures. The exposure to Cu or Chp alone did not induce AChE activity changes, whereas only Cu provoked a significant GST activity increase. Exposure to lower and higher concentration of Chp resulted in MTs content and LPO level increase, respectively. Response of biomarkers to mixtures was generally inconsistent. Data integration by IBR index and PCA revealed different stress levels for given exposure conditions, but no explicit differentiation between single and joint exposures was found. The present results showed that low and environmentally relevant concentrations of Cu and Chp in mixtures may result in a detectable biological response, stressing the need for further investigation of joint effects of widespread marine contaminants in sentinel organisms.


Assuntos
Clorpirifos/farmacologia , Cobre/farmacologia , Mytilus/efeitos dos fármacos , Mytilus/metabolismo , Poluentes Químicos da Água/farmacologia , Animais , Biomarcadores/metabolismo , Interações de Medicamentos
6.
Chemosphere ; 221: 278-291, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30640011

RESUMO

Pesticides used in viticulture create a potential risk for the aquatic environment due to drift during application, runoff and soil leaching. The toxicity of sixteen pesticides and one metabolite were evaluated on the growth of two marine microalgae, Tisochrysis lutea and Skeletonema marinoi, in 96-h exposure assays conducted in microplates. For each substance, concentrations of stock solutions were analytically measured and abiotic assays were performed to evaluate the chemical stability of pesticides in microplates. For two chemicals, microalgae exposures were run simultaneously in microplates and culture flasks to compare EC50 calculated from the two exposure systems. Results from chemical analyses demonstrated the low stability of hydrophobic pesticides (log KOW > 3). For such chemicals, EC50 values calculated using measured pesticide concentrations were two-fold lower than those first estimated using nominal concentrations. Photosystem II inhibitors were the most toxic herbicides, with EC50 values below 10 µg L-1 for diuron and around double this for isoproturon. Chlorpyrifos-methyl was the only insecticide to significantly affect the growth of T. lutea, with an EC50 around 400 µg L-1. All fungicides tested were significantly toxic to both species: strobilurins showed low overall toxicity, with EC50 values around 400 µg L-1, whereas quinoxyfen, and spiroxamine, showed high toxicity to both species, especially to T. lutea, with an EC50 below 1 µg L-1 measured for spiroxamine in culture flasks. This study highlights the need to perform chemical analyses for reliable toxicity assessment and discusses the advantages and disadvantages of using microplates as a toxicity screening tool.


Assuntos
Microalgas/efeitos dos fármacos , Análise em Microsséries/métodos , Praguicidas/toxicidade , Bioensaio , Clorpirifos/análogos & derivados , Clorpirifos/farmacologia , Herbicidas/toxicidade , Microalgas/crescimento & desenvolvimento , Praguicidas/análise , Poluentes Químicos da Água/toxicidade
7.
Rev Argent Microbiol ; 51(1): 3-11, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29885942

RESUMO

This study evaluated the in vitro effect of three concentrations of atrazine, chlorpyrifos and endosulfan on the growth parameters of four non-toxigenic Aspergillus section Flavi strains. The ability of the strains to remove these pesticides in a synthetic medium was also determined. Growth parameters were measured on soil extract solid medium supplied with 5, 10 and 20mg/l of each pesticide, and conditioned to -0.70, -2.78, -7.06 and -10.0 water potential (MPa). Removal assays were performed in Czapek Doc medium (CZD) supplied with 20mg/l of each pesticide under optimal environmental conditions (-2.78 of MPa and 25°C). The residual levels of each pesticide were detected by the reversed-phase HPLC/fluorescence detection system. The lag phases of the strains significantly decreased in the presence of the pesticides with respect to the control media. This result indicates a fast adaptation to the conditions assayed. Similarly, the mycelial growth rates in the different treatments increased depending on pesticide concentrations. Aspergillus oryzae AM 1 and AM 2 strains showed high percentages of atrazine degradation (above 90%), followed by endosulfan (56 and 76%) and chlorpyrifos (50 and 73%) after 30 days of incubation. A significant (p<0.001) correlation (r=0.974) between removal percentages and growth rate was found. This study shows that non-toxigenic Aspergillus section Flavi strains from agricultural soils are able to effectively grow in the presence of high concentrations of atrazine, chlorpyrifos and endosulfan under a wide range of MPa conditions. Moreover, these strains have the ability to remove high levels of these pesticides in vitro in a short time.


Assuntos
Aspergillus flavus/crescimento & desenvolvimento , Aspergillus flavus/metabolismo , Atrazina/administração & dosagem , Atrazina/metabolismo , Clorpirifos/administração & dosagem , Clorpirifos/metabolismo , Endossulfano/administração & dosagem , Endossulfano/metabolismo , Herbicidas/administração & dosagem , Inseticidas/administração & dosagem , Aspergillus flavus/efeitos dos fármacos , Atrazina/farmacologia , Clorpirifos/farmacologia , Relação Dose-Resposta a Droga , Endossulfano/farmacologia , Herbicidas/farmacologia , Inseticidas/farmacologia
8.
Chemosphere ; 219: 671-677, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30557723

RESUMO

Amphibians are considered one of the groups most susceptible to chemical contamination, therefore are good bio-indicators of aquatic pollution. Synergistic effects of temperature and pesticides have been found in amphibians determining amplified toxicity effect on survival and malformations with increasing temperatures. We studied the sensitivity of sublethal concentrations of chlorpyrifos in Rhinella arenarum tadpoles over on two fitness related thermal traits: locomotor swimming performance and thermal tolerance limits (CTmax = critical thermal maximum and CTmin = critical thermal minimum). Our result shows a decrease in the locomotor performance of R. arenarum tadpoles with increasing sublethal chlorpyrifos concentrations. The experimental temperature increased locomotor performance but this being only significant for the control whereas tadpoles raised at any sublethal chlorpyrifos concentration did not increase their total swimming distance with temperature (Concentration × Temperature interaction, P < 0.019). Chlorpyrifos toxicity decreases maximum swimming distance but this reduction not compensated at high temperatures that do enhance swimming performance in the control treatment. On the other hand, higher chlorpyrifos sensitivity in CTmax than CTmin since tadpoles exposed to all polluted treatments exhibits a significant decline in CTmax but not in CTmin. Current global warming and the increase of atypical climatic events, such as heat waves may put at risk the larval chlorpyrifos polluted populations of R. arenarum. Our results show that the sublethal concentrations of the chlorpyrifos pesticide may affect the fitness and survival of the larvae of R. arenarum.


Assuntos
Clorpirifos/farmacologia , Larva/efeitos dos fármacos , Animais , Bufonidae , Clorpirifos/toxicidade , Poluição Ambiental/efeitos adversos , Aquecimento Global , Inseticidas/farmacologia , Inseticidas/toxicidade , Natação , Temperatura Ambiente
9.
Sci Rep ; 8(1): 15279, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30323169

RESUMO

Chlorpyrifos-resistant (Rc) Plutella xylostella (DBM) shows higher wing-vein injury than chlorpyrifos-susceptible (Sm) DBM under heat stress in our previous study. To investigate the toxicological mechanisms of the differences in injury of wing vein between Rc- and Sm-DBM collected from Fuzhou, China, total ten cDNA sequences of wing-development-related genes were isolated and characterized in DBM, including seven open reading frame (ORF) (ash1, ah2, ash3, ase, dpp, srf and dll encoded 187 amino acids, 231 aa, 223aa, 397aa, 423aa, 229aa and 299aa, respectively), and three partly sequences (salm, ser and wnt-1 encoded 614aa, 369aa and 388aa, respectively). The mRNA expression of the genes was inhibited in Rc- and Sm-DBM under heat stress, as compared with that an average temperature (25 °C). And, in general, significantly higher down-regulated expressions of the mRNA expression of the wing development-related genes were found in Rc-DBM as compared to those in Sm-DBM under heat stress. The results indicated that Sm-DBM displayed higher adaptability at high temperature because of significantly lower inhibition the mRNA expressions of wing-development-related genes. We suggest that significantly higher injury of wing vein showed in Rc-DBM under heat stress might be associated with the strong down-regulation of wing-development-related genes.


Assuntos
Clorpirifos/farmacologia , Genes Controladores do Desenvolvimento , Resposta ao Choque Térmico/genética , Resistência a Inseticidas/genética , Lepidópteros , RNA Mensageiro/genética , Asas de Animais/crescimento & desenvolvimento , Animais , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Lepidópteros/embriologia , Lepidópteros/genética , Lepidópteros/crescimento & desenvolvimento , Temperatura Ambiente , Asas de Animais/embriologia , Asas de Animais/metabolismo
10.
PLoS One ; 13(7): e0192628, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30024882

RESUMO

The red palm weevil Rhynchophorus ferrugineus (Olivier) is an important pest of date palms in many regions of the world. This paper reports the first survey of insecticide resistance in field populations of R. ferrugineus in Pakistan which were collected from seven date palm growing areas across Punjab and Khyber Pakhtunkhwa (KPK) provinces, Pakistan. The resistance was assessed by the diet incorporation method against the formulated commonly used chemical insecticides profenophos, imidacloprid, chlorpyrifos, cypermethrin, deltamethrin, spinosad, lambda-cyhalothrin and a fumigant phosphine. Elevated levels of resistance were recorded for cypermethrin, deltamethrin and phosphine after a long history of insecticide use in Pakistan. Resistance Ratios (RRs) were 63- to 79-fold for phosphine, 16- to 74-fold for cypermethrin, 13- to 58-fold for deltamethrin, 2.6- to 44-fold for profenophos, 3- to 24-fold for chlorpyrifos, 2- to 12-fold for lambda-cyhalothrin and 1- to 10-fold for spinosad compared to a susceptible control line. Resistant R. ferrugineus populations were mainly found in southern Punjab and to some extent in KPK. The populations from Bahawalpur, Vehari, Layyah and Dera Ghazi Khan were most resistant to chemical insecticides, while all populations exhibited high levels of resistance to phosphine. Of the eight agents tested, lower LC50 and LC90 values were recorded for spinosad and lambda-cyhalothrin. These results suggest that spinosad and lambda-cyhalothrin exhibit unique modes of action and given their better environmental profile, these two insecticides could be used in insecticide rotation or assist in phasing out the use of older insecticides. A changed pattern of both insecticides can be used sensibly be recommended without evidence of dose rates and frequencies used.


Assuntos
Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/farmacologia , Macrolídeos/farmacologia , Nitrilos/farmacologia , Fosfinas/farmacologia , Piretrinas/farmacologia , Gorgulhos/efeitos dos fármacos , Animais , Clorpirifos/farmacologia , Combinação de Medicamentos , Concentração Inibidora 50 , Resistência a Inseticidas/fisiologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Organotiofosfatos/farmacologia , Paquistão , Phoeniceae/parasitologia , Doenças das Plantas/parasitologia , Gorgulhos/fisiologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-30012402

RESUMO

Fish can be simultaneously or sequentially exposed to various kinds of pollutants, resulting in combined effects. Polycyclic aromatic hydrocarbons induce cytochrome P450 monooxygenase 1A (CYP1A) expression, which catalyzes the conversion of the organophosphorus insecticide chlorpyrifos (CPF) into its most active derivative, CPF-oxon. CPF-oxon inhibits CYP1A and other enzymes, including carboxylesterases (CEs) and acetylcholinesterase (AChE). We studied the effects of an in vivo exposure to crude oil water accommodated fraction (WAF) followed by an ex vivo exposure of liver tissue to CPF on the expression of Cyp1a, AhR and ARNT mRNA, CYP1A protein and on the activity of biomarker enzymes in the rainbow trout (Oncorhynchus mykiss). Juvenile rainbow trout were exposed to WAF (62 µg L-1 TPH) for 48 h. Then, liver was dissected out, sliced and exposed to 20 µg L-1 CPF ex vivo for 1 h. Liver tissue was analyzed for mRNA and protein expression and for CEs, AChE, glutathione S-transferase (GST) and CYP1A (EROD) activity. WAF induced Cyp1a mRNA and CYP1A protein expression by 10-fold and 2.5-8.3-fold, respectively, with no effect of CPF. WAF induced AhR expression significantly (4-fold) in control but not in CPF treated liver tissue. ARNT mRNA expression was significantly lowered (5-fold) by WAF. CPF significantly reduced liver EROD activity, independently of WAF pre-treatment. CEs activity was significantly inhibited in an additive manner following in vivo exposure to WAF (42%) and ex vivo exposure to CPF (19%). CPF exposure inhibited AChE activity (37%) and increased GST activity (42%).


Assuntos
Clorpirifos/toxicidade , Inseticidas/toxicidade , Fígado/efeitos dos fármacos , Oncorhynchus mykiss/fisiologia , Poluição por Petróleo/efeitos adversos , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/química , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Aquicultura , Translocador Nuclear Receptor Aril Hidrocarboneto/antagonistas & inibidores , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Biomarcadores/metabolismo , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Clorpirifos/farmacologia , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/toxicidade , Citocromo P-450 CYP1A1/química , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glutationa Transferase/química , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Inseticidas/farmacologia , Fígado/enzimologia , Fígado/metabolismo , Resíduos de Praguicidas/farmacologia , Resíduos de Praguicidas/toxicidade , Poluentes Químicos da Água/farmacologia
12.
Environ Sci Pollut Res Int ; 25(23): 22903-22910, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29858991

RESUMO

Helicoverpa armigera is a major devastating insect pest on a wide range of vegetables and cash crops. Insecticides are presently indispensable for its control in nearly all crops. H. armigera has acquired resistance against almost all insecticides because of the activity of detoxification enzymes used for the defensive mechanism. The current research was carried out to evaluate the activity of detoxification enzymes, i.e., acetylcholinesterase and alkaline and acid phosphatases in chlorpyrifos-, bifenthrin-, lufenuron-, lambda cyhalothrin-, and emamectin benzoate-treated larvae of H. armigera. The maximum AChE activity was recorded in emamectin benzoate-treated larval samples followed by chlorpyrifos, lufenuron, lambda cyhalothrin and bifenthrin, respectively, while the highest alkaline phosphatases' activity was recorded in emamectin and the lowest in bifenthrin-treated H. armigera. As far as acid phosphatases' activity is concerned, the highest activity was noted in lufenuron samples while the lowest in lambda cyhalothrin samples, respectively. Comparatively, activities of alkaline and acid phosphatases were higher than AChE. The elevated activities of detoxification enzymes can possibly lead to increase in resistance development against synthetic chemical insecticides.


Assuntos
Acetilcolinesterase/metabolismo , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Animais , Clorpirifos/farmacologia , Dissacarídeos/farmacologia , Inativação Metabólica/efeitos dos fármacos , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Mariposas/enzimologia , Nitrilos/farmacologia , Piretrinas/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-29902568

RESUMO

Bivalves are worldwide sentinels of anthropogenic pollution. The inclusion of biomarker responses in chemical monitoring is a recommended practise that has to overcome some difficulties. One of them is the time frame between sample collection and sample processing in order to ensure the preservation of enzymatic activities. In the present study, three bivalve species of commercial interest (mussel, Mytilus galloprovincialis, razor shell, Solen marginatus, and cockle, Cerastoderma edule) were processed within <2 h after being retrieved from their natural habitat, and 24 h after being transported in air under cold conditions (6-8 °C) to laboratory facilities. The enzymatic activities were compared in the three species submitted to both conditions revealing no differences in terms of carboxylesterase dependent activities (CEs) using different substrates: p-nitrophenyl acetate (pNPA), p-nitrophenyl butyrate (pNPB), 1-naphthyl acetate (1-NA), 1-naphthyl butyrate (1-NB) and 2-naphthyl acetate (2-NA). In mussels, three tissues were selected (haemolymph, gills and digestive gland). For comparative purposes, in razor shell and cockle only digestive gland was considered as it is the main metabolic organ. Baseline enzymatic activities for CEs were characterised in the digestive gland of the three bivalves using four out of the five selected CE substrates as well as the kinetic parameters (Vmax and Km) and catalytic efficiency. The in vitro sensitivity to the organophosphorus metabolite chlorpyrifos oxon was also calculated. IC50 values (pM-nM range) were lower than those obtained for vertebrate groups which suggest that bivalves have high protection efficiency against this pesticide as well as species dependent particularities.


Assuntos
Bivalves/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Inibidores da Colinesterase/toxicidade , Sistema Digestório/efeitos dos fármacos , Monitoramento Ambiental/métodos , Resíduos de Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biocatálise/efeitos dos fármacos , Biomarcadores/metabolismo , Bivalves/enzimologia , Bivalves/crescimento & desenvolvimento , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Cardiidae/efeitos dos fármacos , Cardiidae/crescimento & desenvolvimento , Cardiidae/metabolismo , Clorpirifos/análogos & derivados , Clorpirifos/farmacologia , Inibidores da Colinesterase/farmacologia , Sistema Digestório/enzimologia , Sistema Digestório/crescimento & desenvolvimento , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Brânquias/crescimento & desenvolvimento , Hemolinfa/efeitos dos fármacos , Hemolinfa/enzimologia , Mar Mediterrâneo , Mytilus/efeitos dos fármacos , Mytilus/crescimento & desenvolvimento , Mytilus/metabolismo , Naftóis/metabolismo , Compostos Organofosforados/toxicidade , Espanha , Especificidade da Espécie , Especificidade por Substrato
14.
Environ Health Perspect ; 126(4): 047009, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29681141

RESUMO

BACKGROUND: Organophosphorus (OP) compounds are the most widely used group of insecticides in the world. Risk assessments for these chemicals have focused primarily on 10% inhibition of acetylcholinesterase in the brain as the critical metric of effect. Aside from cholinergic effects resulting from acute exposure, many studies suggest a linkage between cognitive deficits and long-term OP exposure. OBJECTIVE: In this proof-of-concept study, we focused on one of the most widely used OP insecticides in the world, chlorpyrifos (CPF), and utilized an existing physiologically based pharmacokinetic (PBPK) model and a novel pharmacodynamic (PD) dose-response model to develop a point of departure benchmark dose estimate for cognitive deficits following long-term, low-dose exposure to this chemical in rodents. METHODS: Utilizing a validated PBPK/PD model for CPF, we generated a database of predicted biomarkers of exposure and internal dose metrics in both rat and human. Using simulated peak brain CPF concentrations, we developed a dose-response model to predict CPF-induced spatial memory deficits and correlated these changes to relevant biomarkers of exposure to derive a benchmark dose specific to neurobehavioral changes. We extended these cognitive deficit predictions to humans and simulated corresponding exposures using a model parameterized for humans. RESULTS: Results from this study indicate that the human-equivalent benchmark dose (BMD) based on a 15% cognitive deficit as an end point is lower than that using the present threshold for 10% brain AChE inhibition. This predicted human-equivalent subchronic BMD threshold compares to occupational exposure levels determined from biomarkers of exposure and corresponds to similar exposure conditions where deficits in cognition are observed. CONCLUSIONS: Quantitative PD models based on neurobehavioral testing in animals offer an important addition to the methodologies used for establishing useful environmental public health indicators and BMDs, and predictions from such models could help inform the human health risk assessment for chlorpyrifos. https://doi.org/10.1289/EHP1743.


Assuntos
Clorpirifos/toxicidade , Disfunção Cognitiva/induzido quimicamente , Saúde Ambiental/métodos , Inseticidas/toxicidade , Saúde Pública/métodos , Animais , Benchmarking , Clorpirifos/farmacocinética , Clorpirifos/farmacologia , Relação Dose-Resposta a Droga , Humanos , Inseticidas/farmacocinética , Inseticidas/farmacologia , Modelos Biológicos , Estudo de Prova de Conceito , Ratos
15.
Environ Sci Pollut Res Int ; 25(17): 17033-17037, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29633191

RESUMO

Red cotton bug, Dysdercus koenigii (Hemiptera: Pyrrhocoridae), has become the major insect pest of various crops, including cotton, and thereby reducing the yield qualitatively and quantitatively and synthetic insecticides belonging to different groups are the major control agents for such insect pests. A laboratory experiment was carried out to evaluate the effect of different conventional insecticides, i.e., imidacloprid, deltamethrin, lambda cyhalothrin, gamma cyhalothrin and cyfluthirn on haemocytes of D. koenigii. The individuals were exposed to insecticides separately and data was recorded after 30 and 60 min of the exposure. The findings of current study depicted chlorpyrifos to be more effective and significant alterations in total haemocyte counts and differential haemocyte counts were observed in the cyfluthirn treated D. koenigii. In addition to this, cell structure was also disrupted as an immune response. Similar studies would also be helpful to understand the defence mechanisms of insects against the xenobiotics which will help to device efficient management tools for D. koenigii.


Assuntos
Clorpirifos/farmacologia , Hemípteros/efeitos dos fármacos , Heterópteros/efeitos dos fármacos , Inseticidas/farmacologia , Neonicotinoides/química , Nitrilos/química , Nitrocompostos/química , Piretrinas/química , Animais
16.
Chemosphere ; 205: 209-214, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29698832

RESUMO

The terciopelo (Bothrops asper), is one of the most important venomous snakes in Costa Rica and common on agriculture where insecticides are frequently used for pest control. To assess the exposure to organophosphates on captive B. asper, an experiment using chlorpyrifos and butyrylcholinesterase (BChE), as a biomarker was conducted. In addition to BChE, hematology, aspartate aminotransferase (AST), total proteins (TP) and albumin were measured after exposure. Different concentrations of chlorpyrifos were used in Group A (0.1%) and B (1%), while the Control Group received distilled water; each group was composed of 5 snakes. Values of BChE, AST, TP, and albumin were measured before exposure, and at 6, 12, 24, 196, 360 and 528 h post-exposure. Hematology values were measured after 24 h post-exposure. As result, an important variation between subjects in all groups before exposure was obtained. Moreover, BChE activity showed 37% inhibition of Group A when compared to Control Group at 12 h post-exposure, and a higher inhibition of Group B (97%) related to Control Group, at 6 h post-exposure. Recovery of BChE occurred towards 528 h, never reaching initial values. Despite some variation in the rest of parameters used, a marked relative lymphopenia and monocytosis occurred at 24 h, assuming stress as the main cause.


Assuntos
Biomarcadores/metabolismo , Análise Química do Sangue/veterinária , Bothrops/fisiologia , Butirilcolinesterase/metabolismo , Clorpirifos/farmacologia , Hematologia , Animais , Bothrops/sangue , Butirilcolinesterase/química , Costa Rica , Feminino , Inseticidas/farmacologia , Masculino
17.
J Biochem Mol Toxicol ; 32(5): e22050, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29667781

RESUMO

The theme of the present work is to evaluate the protective effect of nanoencapsulated quercetin (NEQ) against chlorpyrifos (CPF)-induced hepatic damage and immune alterations in animals. Nanoparticles (NP) drug encapsulation was prepared. Forty male Wistar rats were divided into eight groups. Two groups served as control and CPF (13.5 mg/kg) treatment for 28 days. Other three groups were free quercetin (QC), NP and NEQ treated with 3 mg/kg respectively for 15 days; whereas remaining three groups received treatment of CPF and QC, NP, NEQ, respectively, for 15 days. The results show that significantly altered oxidative stress in the liver tissue and liver enzyme parameters in blood and immune responses in CPF-treated rats compared to controls. Administration of NEQ attenuated biochemical and immunological parameters. The liver histopathological analysis confirmed pathological improvement. Hence, use of NEQ appeared to be beneficial to a great extent in attenuating and restoring hepatic oxidative damage and immune alteration sustained by pesticide exposure.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Clorpirifos/efeitos adversos , Flavonoides/farmacologia , Fígado/imunologia , Nanocápsulas , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Clorpirifos/farmacologia , Fígado/patologia , Masculino , Ratos , Ratos Wistar
18.
Pest Manag Sci ; 74(11): 2450-2459, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29575759

RESUMO

BACKGROUND: Characterizing lethal and sublethal control of soil-based pests with plant protection products is particularly challenging due to the complex and dynamic interplay of the system components. Here, we present two types of studies: acute toxcity experiments (homogenous exposure of individuals in soil) and rhizotron experiments (heterogeneous exposure of individuals in soil) to investigate their ability to strengthen our understanding of mechanisms driving the effectivness of the plant protection product. Experiments were conducted using larvae of the western corn rootworm Diabrotica virgifera LeConte and three pesticide active ingredients: clothianidin (neonicotinoid), chlorpyrifos (organophosphate) and tefluthrin (pyrethroid). RESULTS: The order of compound concentrations needed to invoke a specific effect intensity (EC50 values) within the acute toxicity tests was chlorpyrifos > tefluthrin > clothianidin. This order changed for the rhizotron experiments because application type, fate and transport of the compounds in the soil profile, and sublethal effects on larvae also influence their effectiveness in controlling larval feeding on corn roots. CONCLUSION: Beyond the pure measurement of efficacy through observing relative changes in plant injury to control plants, the tests generate mechanistic understanding for drivers of efficacy apart from acute toxicity. The experiments have the potential to enhance efficacy testing and product development, and might be useful tools for assessing resistance development in the future. © 2018 Society of Chemical Industry.


Assuntos
Clorpirifos/farmacologia , Besouros/efeitos dos fármacos , Ciclopropanos/farmacologia , Guanidinas/farmacologia , Hidrocarbonetos Fluorados/farmacologia , Inseticidas/farmacologia , Neonicotinoides/farmacologia , Tiazóis/farmacologia , Animais , Besouros/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Raízes de Plantas , Testes de Toxicidade Aguda , Zea mays
19.
Chemosphere ; 199: 26-34, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29427811

RESUMO

In this study, the cDNA fragments of cytokines (il-8) and toll-like receptor (TLR) pathway signaling molecules (myd88, irak-1, irf5, and irf7) in the Chinese rare minnow were cloned and exhibited a high amino-acid sequence identity compared to other cyprinid fish orthologs. The mRNA expressions of these genes in the different tissues (liver, brain, spleen, kidney, and skin) were observed. The highest expression levels of myd88, irak-1, and irf5 were detected in the spleen, whereas il-8 and irf7 were detected in the kidney and liver respectively. The mRNA expression of irak-1, irf5, and irf7 in the liver from 0.1 µg/L and 0.5 µg/L CPF treatments were significantly increased on day 7 (p < 0.05), whereas the levels of only irak-1 and irf7 were markedly increased on day 28 (p < 0.05). Moreover, the mRNA expression of il-8 in the spleen following 0.5 µg/L CPF treatments was significantly decreased on day 7 (p < 0.05), whereas significantly decrease were observed in the levels of irf7 in the spleen at 2.5 µg/L CPF on days 7 and 28 (p < 0.05). The 0.1 µg/L and 0.5 µg/L of CPF significantly induced the levels of irak-1 and myd88 in the spleen after 28 d exposure (p < 0.05). Therefore, the high induction of cytokines and TLR pathway signaling molecules demonstrated that Chinese rare minnow was immune-compromised exposed to CPF. Moreover, our finding indicated that these immune-related genes could be feasible to screen for substances hazardous to the immune system of fish.


Assuntos
Cyprinidae , Citocinas/genética , Transdução de Sinais , Receptores Toll-Like/metabolismo , Sequência de Aminoácidos , Animais , Clorpirifos/farmacologia , Cyprinidae/imunologia , Cyprinidae/metabolismo , Citocinas/metabolismo , DNA Complementar/metabolismo , Inseticidas , Fatores de Tempo , Distribuição Tecidual
20.
Nat Commun ; 9(1): 837, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29483531

RESUMO

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities of schistosome-infected snails by increasing the algae snails eat and decreasing densities of snail predators. Epidemiological models indicate that these agrochemical effects can increase transmission of schistosomes. Identifying agricultural practices or agrochemicals that minimize disease risk will be critical to meeting growing food demands while improving human wellbeing.


Assuntos
Agroquímicos/farmacologia , Astacoidea/efeitos dos fármacos , Heterópteros/efeitos dos fármacos , Schistosoma haematobium/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/veterinária , Caramujos/efeitos dos fármacos , Animais , Astacoidea/fisiologia , Atrazina/farmacologia , Clorpirifos/farmacologia , Cricetinae , Ecossistema , Fertilizantes/toxicidade , Cadeia Alimentar , Heterópteros/fisiologia , Humanos , Contagem de Ovos de Parasitas , Perifíton/efeitos dos fármacos , Perifíton/fisiologia , Fitoplâncton/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Tanques , Risco , Schistosoma haematobium/crescimento & desenvolvimento , Schistosoma mansoni/crescimento & desenvolvimento , Esquistossomose/parasitologia , Esquistossomose/transmissão , Caramujos/parasitologia
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