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1.
Environ Toxicol ; 35(10): 1091-1099, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32485069

RESUMO

Various pollutants co-exist in the aquatic environment such as carbamazepine (CBZ) and copper (Cu), which can cause complex effects on inhabiting organisms. The toxic impacts of the single substance have been studied extensively. However, the studies about their combined adverse impacts are not enough. In the present study, zebrafish were exposed to environmental relevant concentrations of CBZ (1, 10, and 100 µg/L), Cu (0.5, 5, and 10 µg/L) and the mixtures (1 µg/L CBZ + 0.5 µg/L Cu, 10 µg/L CBZ + 5 µg/L Cu, 100 µg/L CBZ + 10 µg/L Cu) for 45 days, the effects on nervous and antioxidant systems of zebrafish were investigated. The results demonstrated that, in comparison with single exposure group, the combined presence of CBZ and Cu exacerbated the effect of antioxidant system (the ability of inhibition of hydroxyl radicals (IHR), superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST)) but not nervous system (Acetylcholinesterase [AChE]). The qPCR results supported the changes of corresponding enzymes activities. Hepatic histopathological analysis verified the results of biomarkers. Our work illustrated that the toxicity of mixed pollutants is very complicated, which cannot simply be inferred from the toxicity of single pollutant, and calls for more co-exposure experiments to better understanding of the co-effects of pollutants on aquatic organisms.


Assuntos
Antioxidantes/metabolismo , Carbamazepina/toxicidade , Cobre/toxicidade , Sistema Nervoso/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Catalase/genética , Catalase/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Sistema Nervoso/enzimologia , Sistema Nervoso/metabolismo , Estresse Oxidativo/genética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
2.
Parasit Vectors ; 13(1): 152, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209131

RESUMO

BACKGROUND: Progress made in the control of malaria vectors globally is largely due to the use of insecticides. However, success in the fight against malaria has slowed down or even stalled due to a host of factors including insecticide resistance. The greatest burden of the disease is felt in Africa, particularly Nigeria. Unfortunately, adequate information on insecticide resistance is lacking in many parts of the country, particularly the South-East Zone. Hence, this study aims to bridge the information gap in the Zone. METHODS: The study was conducted from April to December 2016. Anopheles gambiae (s.l.) larvae and pupae were collected from one community each, in the five states of the South-East Zone and reared to the adult stage. The adults were subjected to bioassays for insecticide resistance in accordance with the World Health Organization test procedures, across the four classes of insecticides used in public health. The mosquitoes were also subjected to molecular identification to the species level, and genotyped for West African knockdown resistance mutation (L1014F) and insensitive acetylcholinesterase-1 resistance mutation (G119S). RESULTS: The mosquitoes were susceptible (100%) to bendiocarb but resistant to pirimiphos-methyl (39.6%), deltamethrin (57%) and dichlorodiphenyltrichloroethane (DDT) (13%). Molecular analysis revealed that only An. gambiae (sensu stricto) was found in all the states except for Ebonyi, where only Anopheles coluzzii was present. High frequencies (0.6-0.9) of the L1014F mutation were found across the zone. The L1014F mutation was significantly higher in An. gambiae (s.s.) than in An. coluzzii (P < 0.0001). A relatively low frequency (0.2) of the G119S mutation was found in An. coluzzii, and only in Ebonyi State. CONCLUSION: The results show that mosquitoes collected from the South-East Zone of Nigeria were resistant to all insecticides used, except for bendiocarb. The presence of L1014F and G119S resistance mutations reported in this study calls for urgent attention to stop the growing threat of insecticide resistance in the country.


Assuntos
Anopheles/efeitos dos fármacos , Anopheles/genética , Resistência a Inseticidas/efeitos dos fármacos , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Acetilcolinesterase/genética , Animais , DDT , Feminino , Técnicas de Silenciamento de Genes , Larva/efeitos dos fármacos , Malária , Mosquitos Vetores/genética , Mutação , Nigéria , Nitrilos , Compostos Organotiofosforados/farmacologia , Fenilcarbamatos/farmacologia , Pupa/efeitos dos fármacos , Piretrinas , Organização Mundial da Saúde
3.
Eur J Med Chem ; 191: 112140, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32088494

RESUMO

2,3-Dihydro-5,6-dimethoxy-2-[4-(4-alkyl-4-methylpiperazinium-1-yl)benzylidine]-1H-inden-1-one halide salt derivatives as a novel donepezil hybrid analogs with the property of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzyme inhibition were designed and synthesized via N-alkylation reaction of 2,3-dihydro-5,6-dimethoxy-2-[4-(4-methylpiperazin-1-yl)benzylidene]-1H-inden-1-one with some alkyl halides. Biological tests demonstrated that most of the synthesized compounds have moderate to good inhibitory activities effect on cholinesterase enzymes. Among them, 10e showed the best profile as a selected compound for inhibition of hAChE (IC50 = 0.32) and hBuChE (IC50 = 0.43 µM) enzymes. Kinetic analysis and molecular docking led to a better understanding of this compound. Kinetic studies disclosed that 10e inhibited acetylcholinesterase in mixed-type and butyrylcholinesterase in non-competitive type. The toxicity results showed that 10e is less toxic than donepezil and has better inhibitory activity against hBuChE when compared to donepezil or Galantamine. Other performed experiments revealed that 10e has an anti-ß amyloid effect which is capable of reducing ROS, LDH and MDA also possing positive effect on TAC. On the other hand, it has shown a good anti-inflammation effect.


Assuntos
Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Indenos/farmacologia , Piperazinas/farmacologia , Acetilcolinesterase/genética , Algoritmos , Butirilcolinesterase/genética , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Indenos/síntese química , Indenos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Sais/síntese química , Sais/química , Sais/farmacologia , Relação Estrutura-Atividade
4.
Parasitol Int ; 76: 102066, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32006676

RESUMO

Trypanosoma cruzi infection triggers an intense production of pro-inflammatory cytokines mediated by T helper 1 lymphocytes, inducing the anti-inflammatory reflex of acetylcholine (ACh). The ACh concentration modulation is associated to the two major esterases, the acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). AChE H353N protein polymorphism is related to low Chagas chronic disease prognostic. In order to evaluate the correlation of plasmatic BuChE concentration and the presence of AChE H353N polymorphism in Chagas disease patients and healthy individuals, we studied two groups of individuals, one of 61 Chagas disease patients and another of 74 healthy individuals. Plasma concentration of BuChE was measured by the chemiluminescent method and AChE H353N polymorphism was investigated by PCR-RFLP and sequencing of the respective encoding AChE gene fragment. The BuChE concentration was statistically higher in Chagas disease patients, with no AChE genotype significant influence. AChE genotypes YT*A/YT*A, YT*A/YT*B and YT*B/YT*B, respectively, were expressed in 53 (86.88%), 7 (11.46%) and one (1.64%) chagasic patients, and in 68 (91.89%), 6 (8.10%) and none healthy individuals. BuChE activity may represent an important marker for chronic Chagas disease inflammatory process and prognostic. Lower BuChE concentration correlated with AChE YT*B allele, although without statistical power.


Assuntos
Acetilcolinesterase/genética , Butirilcolinesterase/sangue , Doença de Chagas/enzimologia , Inflamação , Polimorfismo Genético , Adulto , Idoso , Alelos , Biomarcadores/sangue , Doença de Chagas/genética , Doença Crônica , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
5.
Sci Rep ; 10(1): 1658, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015353

RESUMO

Colonic diverticulosis is a very common condition. Many patients develop diverticulitis or other complications of diverticular disease. Recent genome-wide association studies (GWAS) consistently identified three major genetic susceptibility factors for both conditions, but did not discriminate diverticulititis and diverticulosis in particular due the limitations of registry-based approaches. Here, we aimed to confirm the role of the identified variants for diverticulosis and diverticulitis, respectively, within a well-phenotyped cohort of patients who underwent colonoscopy. Risk variants rs4662344 in Rho GTPase-activating protein 15 (ARHGAP15), rs7609897 in collagen-like tail subunit of asymmetric acetylcholinesterase (COLQ) and rs67153654 in family with sequence similarity 155 A (FAM155A) were genotyped in 1,332 patients. Diverticulosis was assessed by colonoscopy, and diverticulitis by imaging, clinical symptoms and inflammatory markers. Risk of diverticulosis and diverticulitis was analyzed in regression models adjusted for cofactors. Overall, the variant in FAM155A was associated with diverticulitis, but not diverticulosis, when controlling for age, BMI, alcohol consumption, and smoking status (ORadjusted 0.49 [95% CI 0.27-0.89], p = 0.002). Our results contribute to the assessment specific genetic variants identified in GWAS in the predisposition to the development of diverticulitis in patients with diverticulosis.


Assuntos
Doença Diverticular do Colo/genética , Diverticulose Cólica/genética , Proteínas de Membrana/genética , Acetilcolinesterase/genética , Idoso , Estudos de Coortes , Colágeno/genética , Feminino , Proteínas Ativadoras de GTPase/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Alemanha , Humanos , Lituânia , Masculino , Pessoa de Meia-Idade , Proteínas Musculares/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco
6.
J Clin Neurosci ; 72: 238-243, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31889643

RESUMO

BACKGROUND: To ascertain the frequency, clinical spectrum and outcome of congenital myasthenic syndrome (CMS) patients who reported to the neuromuscular division of our quaternary medical center during the past ten years. METHODS: We performed a retrospective analysis of all the CMS patients who reported to us during the study period. RESULTS: Twenty-one patients of CMS attended our quaternary hospital over the past ten years. The median follow-up was 24 (IQR: 16.5-67.3) months. All the patients showed an overall improvement in the last follow up. The diagnosis of CMS could be genetically confirmed in seven cases. Four patients had COLQ mutation, two had CHRNε mutation and one had MUSK mutation. All the cases of COLQ mutation and one case of MUSK mutation had a limb-girdle (LG) presentation. Our study and review of literature imply that CMS should be suspected in cases of seronegative myasthenia gravis cases if the onset is at less than 20 years and strongly so if the onset is within the first two years of life. In addition, a positive family history, delayed motor milestones, and a poor response to immune-modulators should be actively sought for as indicators of CMS.


Assuntos
Testes Genéticos/estatística & dados numéricos , Síndromes Miastênicas Congênitas/genética , Acetilcolinesterase/genética , Pré-Escolar , Colágeno/genética , Feminino , Testes Genéticos/normas , Humanos , Índia , Lactente , Masculino , Proteínas Musculares/genética , Mutação , Síndromes Miastênicas Congênitas/epidemiologia , Síndromes Miastênicas Congênitas/patologia , Receptores Proteína Tirosina Quinases/genética , Receptores Colinérgicos/genética
7.
PLoS One ; 15(1): e0227631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945778

RESUMO

Currently prescribed medications for the treatment of Alzheimer's disease (AD) that are based on acetylcholinesterase inhibition only offer symptomatic relief but do not provide protection against neurodegeneration. There appear to be an intense need for the development of therapeutic strategies that not only improve brain functions but also prevent neurodegeneration. The oxidative stress is one of the main causative factors of AD. Various antioxidants are being investigated to prevent neurodegeneration in AD. The objective of this study was to investigate the neuroprotective effects of naringenin (NAR) against AlCl3+D-gal induced AD-like symptoms in an animal model. Rats were orally pre-treated with NAR (50 mg/kg) for two weeks and then exposed to AlCl3+D-gal (150 mg/kg + 300 mg/kg) intraperitoneally for one week to develop AD-like symptoms. The standard drug, donepezil (DPZ) was used as a stimulator of cholinergic activity. Our results showed that NAR pre-treatment significantly protected AD-like behavioral disturbances in rats. In DPZ group, rats showed improved cognitive and cholinergic functions but the neuropsychiatric functions were not completely improved and showed marked histopathological alterations. However, NAR not only prevented AlCl3+D-gal induced AD-like symptoms but also significantly prevented neuropsychiatric dysfunctions in rats. Results of present study suggest that NAR may play a role in enhancing neuroprotective and cognition functions and it can potentially be considered as a neuroprotective compound for therapeutic management of AD in the future.


Assuntos
Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Flavanonas/farmacologia , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/prevenção & controle , Acetilcolinesterase/genética , Cloreto de Alumínio/toxicidade , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Função Executiva/efeitos dos fármacos , Galactose/toxicidade , Masculino , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
8.
Biosens Bioelectron ; 148: 111825, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677527

RESUMO

Acetylcholinesterase (AChE) has been widely applied on the enzyme inhibition-based detection of organophosphate pesticides (OPs). To improve the sensitivity of fluorometric OPs assay, great efforts were made to change the fluorometric probes or analytical strategies rather than improve the sensitivity of AChE towards OPs. In this work, AChE wild-type (WT) and mutants (E69Y and E69Y/F330L) from Drosophila were successfully displayed on the surface of yeast through a-agglutinin-mediated microbial surface display system. The location of AChE on yeast surface was confirmed by immunofluorescence analysis. Further, a fluorescence OPs detection method was developed by combining yeast surface-displayed AChE mutants and protein-directed electronegative fluorescent gold nanoclusters (Au NCs). Yeast surface-displayed AChE can catalyze the hydrolysis of acetylthiocholine to produce thiocholine. The electropositive thiocholine can not only bind with AuNCs by Au-S bond but also absorb Au NCs by the electrostatic interaction, leading to the aggregation of AuNCs and corresponding fluorescence quenching. When AChE was incubated with paraoxon, a typical model of OPs, the activity of AChE was inhibited and the thiocholine-induced aggregation of AuNCs was reduced. The fluorescence assay based on Au NCs and yest-AChE-E69Y/F330L exhibited the ultra-sensitivity for ultra-trace OPs and 2-6 orders of magnitude lower detection limit (3.3 × 10-14 M) than those of AChE-WT-based method and other reported methods. In addition, the proposed method showed excellent reliability for the real samples assay. This work would provide an alternative strategy for the improvement of bio-analysis at its source.


Assuntos
Acetilcolinesterase/genética , Técnicas Biossensoriais/métodos , Drosophila melanogaster/enzimologia , Compostos Organofosforados/análise , Praguicidas/análise , Saccharomyces cerevisiae/genética , Acetilcolinesterase/metabolismo , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Mutagênese Sítio-Dirigida , Mutação , Compostos Organofosforados/metabolismo , Praguicidas/metabolismo , Saccharomyces cerevisiae/metabolismo
9.
Biochim Biophys Acta Proteins Proteom ; 1868(1): 140270, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518689

RESUMO

A new spectrofluorimetric method more sensitive than the Ellman method was developed for determination of both acetylcholinesterase and butyrylcholinesterase activity and for kinetic analysis of these enzymes and their mutants. Two selected mutants of human butyrylcholinesterase (E197Q and E197G) were included in this work. As for the Ellman's method, substrates are thiocholine esters, but the chromogenic reagent, DTNB (dithio-bisnitro benzoic acid) is replaced by a fluorogenic probe, "Calbiochem Probe IV", (3-(7-Hydroxy-2-oxo-2H-chromen-3-ylcarbamoyl)acrylic acid methylester). Compared to the classical Ellman's method, the sensitivity of this new spectrofluorimetric assay is 2 orders of magnitude higher. The method allows measurement of activity in media containing <10-11 M of cholinesterase active sites at low substrate concentrations, either under first order conditions, [S] << Km, or under conditions where kinetics obeys the Michaelis-Menten model, i.e. at [S] < 1 mM for wild-type enzymes. The method adapted to titration plate reader assays is suitable for clinical and toxicological routine analyses, for high throughput screening of novel cholinesterase mutants and screening of inhibitor libraries of pharmacological interest.


Assuntos
Acetilcolinesterase/química , Butirilcolinesterase/química , Acetilcolinesterase/genética , Acetiltiocolina/análogos & derivados , Acetiltiocolina/química , Butirilcolinesterase/genética , Butiriltiocolina/química , Catálise , Humanos , Cinética , Simulação de Acoplamento Molecular , Mutação , Espectrometria de Fluorescência
10.
BMC Pharmacol Toxicol ; 20(Suppl 1): 83, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31852533

RESUMO

BACKGROUND: Exposure to vinylcyclohexene (VCH) and methylmercury (MeHg+) can induce oxidative stress and gene modulation. Several studies have been evaluating the effects of VCH and MeHg+, but little is known about interactive effects between them. This work aimed to assess the exposure and co-exposure effects of MeHg+ and VCH on oxidative stress and gene modulation in Drosophila melanogaster. METHODS: Reactive species production, glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities were evaluated after exposure and co-exposure to VCH (1 mM) and MeHg+ (0.2 mM) for one or three days in the head and body (thorax and abdomen) of flies. The expression of genes related to redox state and inflammatory response was evaluated after exposure and co-exposure to VCH and MeHg+ for three days. RESULTS: Survival decreased only in flies co-exposed to VCH and MeHg+ for three days. All treatments increased total reactive species production after one day of exposure. However, no significant changes were observed in the head after three days of exposure. One day of exposure to VCH caused an increase in the head GST activity, whereas MeHg+ induced an increase after three days of exposure. Regarding the body, all treatments increased GST activity after one day of exposure, but only the flies exposed to MeHg+ presented an increase in GST activity after three days of exposure. Treatments did not alter AChE activity in the head. As for gene expression, there was a significant increase in the Relish transcription factor gene in the flies' body, but Nrf2, Keap1, Jafrac1, TrxR1, and NF-κß were not altered. CONCLUSION: The results suggest that exposure to VCH and MeHg+ induce oxidative stress and activation of an inflammatory response in fruit flies.


Assuntos
Cicloexenos/toxicidade , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Cicloexenos/administração & dosagem , Relação Dose-Resposta a Droga , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Sinergismo Farmacológico , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Compostos de Metilmercúrio/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética
11.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683670

RESUMO

Asatone and isoasatone A from Asarum ichangense Cheng were determined to be defensive compounds to some insects in a previous investigation. However, the anti-insect activity mechanisms to caterpillar are still unclear. The compounds asatone and isoasatone A from A. ichangense were induced by Spodoptera litura. The anti-insect activity of asatone and isoasatone A to S. litura was further tested by weight growth rate of the insect through a diet experiment. Isoasatone A showed a more significant inhibitory effect on S. litura than asatone on the second day. The concentration of asatone was higher than isoasatone A in the second instar larvae of S. litura after 12 h on the feeding test diet. Both compounds caused mid-gut structural deformation and tissue decay as determined by mid-gut histopathology of S. litura. Furthermore, some detoxification enzyme activity were measured by relative expression levels of genes using a qPCR detecting system. Asatone inhibited the gene expression of the cytochrome P450 monooxygenases (P450s) CYP6AB14. Isoasatone A inhibited the relative expression levels of CYP321B1, CYP321A7, CYP6B47, CYP6AB14, and CYP9A39. Asatone increased the relative gene expression of the glutathione transferases (GSTs) SIGSTe1 and SIGSTo1, in contrast, isoasatone A decreased the relative gene expression of SIGSTe1 by about 33 fold. Neither compound showed an effect on acetylcholinesterase SIAce1 and SIAce2. The mechanism of anti-insect activity by both compounds could be explained by the inhibition of enzymes P450s and GSTs. The results provide new insights into the function of unique secondary metabolites asatone and isoasatone A in genus Asarum, and a new understanding of why A. ichangense is largely free of insect pests.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa Transferase/metabolismo , Lignanas/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/enzimologia , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Asarum/química , Sistema Enzimático do Citocromo P-450/genética , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Lignanas/química , Spodoptera/genética
12.
Genes (Basel) ; 10(10)2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614683

RESUMO

Growing resistance is reported to carbamate insecticides in malaria vectors in Cameroon. However, the contribution of acetylcholinesterase (Ace-1) to this resistance remains uncharacterised. Here, we established that the G119S mutation is driving resistance to carbamates in Anopheles gambiae populations from Cameroon. Insecticide bioassay on field-collected mosquitoes from Bankeng, a locality in southern Cameroon, showed high resistance to the carbamates bendiocarb (64.8% ± 3.5% mortality) and propoxur (55.71% ± 2.9%) but a full susceptibility to the organophosphate fenitrothion. The TaqMan genotyping of the G119S mutation in field-collected adults revealed the presence of this resistance allele (39%). A significant correlation was observed between the Ace-1R and carbamate resistance at allelic ((bendiocarb; odds ratio (OR) = 75.9; p < 0.0001) and (propoxur; OR = 1514; p < 0.0001)) and genotypic (homozygote resistant vs. homozygote susceptible (bendiocarb; OR = 120.8; p < 0.0001) and (propoxur; OR = 3277; p < 0.0001)) levels. Furthermore, the presence of the mutation was confirmed by sequencing an Ace-1 portion flanking codon 119. The cloning of this fragment revealed a likely duplication of Ace-1 in Cameroon as mosquitoes exhibited at least three distinct haplotypes. Phylogenetic analyses showed that the predominant Ace-1R allele is identical to that from West Africa suggesting a recent introduction of this allele in Central Africa from the West. The spread of this Ace-1R represents a serious challenge to future implementation of indoor residual spraying (IRS)-based interventions using carbamates or organophosphates in Cameroon.


Assuntos
Acetilcolinesterase/genética , Anopheles/genética , Resistência a Inseticidas/genética , Acetilcolinesterase/metabolismo , Animais , Anopheles/efeitos dos fármacos , Anopheles/patogenicidade , Camarões , Carbamatos/metabolismo , Carbamatos/farmacologia , Vetores de Doenças , Fenitrotion , Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/farmacologia , Malária/transmissão , Controle de Mosquitos , Mosquitos Vetores , Mutação/efeitos dos fármacos , Fenilcarbamatos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Propoxur
13.
J Agric Food Chem ; 67(44): 12182-12190, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31609606

RESUMO

In continuation of our program to develop natural-product-based pesticidal candidates, matrinic/oxymatrinic amides were obtained through structural optimization of matrine. N'-(4-Fluoro)phenyl-N-(4-bromo)phenylsulfonyloxymatrinic amide (IIm) showed potent insecticidal activity against Mythimna separata. N-(Un)substituted phenylsulfonylmatrinic acids (3a-c) exhibited promising acaricidal activity against Tetranychus cinnabarinus. By qRT-PCR analysis of nAChR subunits and AChE genes and determination of AChE activity of (un)treated T. cinnabarinus, it suggested that the open lactam ring of matrine and carboxyl group and (4-methyl)phenylsulfonyl of N-(4-methyl)phenylsulfonylmatrinic acid (3b) were necessary for action with α2, α4, α5, and ß3 nAChR subunits; compound 3b was an inhibitor of AChE in T. cinnabarinus, and AChE was one possible target of action in T. cinnabarinus against 3b; and compound 3b may be an antagonist of nAChR and AChE in T. cinnabarinus.


Assuntos
Acaricidas/química , Alcaloides/química , Amidas/química , Inseticidas/química , Quinolizinas/química , Acaricidas/síntese química , Acaricidas/farmacologia , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Alcaloides/farmacologia , Amidas/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Feminino , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inseticidas/síntese química , Inseticidas/farmacologia , Estrutura Molecular , Mariposas/efeitos dos fármacos , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Quinolizinas/farmacologia , Relação Estrutura-Atividade , Tetranychidae/efeitos dos fármacos , Tetranychidae/genética , Tetranychidae/crescimento & desenvolvimento , Tetranychidae/metabolismo
14.
Proc Natl Acad Sci U S A ; 116(42): 21012-21021, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31575743

RESUMO

Insecticides allow control of agricultural pests and disease vectors and are vital for global food security and health. The evolution of resistance to insecticides, such as organophosphates (OPs), is a serious and growing concern. OP resistance often involves sequestration or hydrolysis of OPs by carboxylesterases. Inhibiting carboxylesterases could, therefore, restore the effectiveness of OPs for which resistance has evolved. Here, we use covalent virtual screening to produce nano-/picomolar boronic acid inhibitors of the carboxylesterase αE7 from the agricultural pest Lucilia cuprina as well as a common Gly137Asp αE7 mutant that confers OP resistance. These inhibitors, with high selectivity against human acetylcholinesterase and low to no toxicity in human cells and in mice, act synergistically with the OPs diazinon and malathion to reduce the amount of OP required to kill L. cuprina by up to 16-fold and abolish resistance. The compounds exhibit broad utility in significantly potentiating another OP, chlorpyrifos, against the common pest, the peach-potato aphid (Myzus persicae). These compounds represent a solution to OP resistance as well as to environmental concerns regarding overuse of OPs, allowing significant reduction of use without compromising efficacy.


Assuntos
Resistência a Inseticidas/genética , Inseticidas/farmacologia , Acetilcolinesterase/genética , Animais , Afídeos/efeitos dos fármacos , Hidrolases de Éster Carboxílico/genética , Linhagem Celular , Diazinon/farmacologia , Feminino , Células HEK293 , Humanos , Malation/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Organofosfatos/farmacologia
15.
Environ Sci Pollut Res Int ; 26(29): 30508-30523, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463743

RESUMO

The presence of natural organic matter such as humic acid (HA) can influence the behavior of graphene oxide (GO) in the aquatic environment. In this study, zebrafish embryos were analyzed after 5 and 7 days of exposure to GO (100 mg L-1) and HA (20 mg L-1) alone or together. The results indicated that, regardless of the presence of HA, larvae exposed to GO for 5 days showed an increase in locomotor activity, reduction in the yolk sac size, and total length and inhibition of AChE activity, but there was no difference in enzyme expression. The statistical analysis indicated that the reductions in total larval length, yolk sac size, and AChE activity in larvae exposed to GO persisted in relation to the control group, but there was a recovery of these parameters in groups also exposed to HA. Larvae exposed to GO for 7 days did not show significant differences in locomotor activity, but the RT-PCR gene expression analysis evidenced an increase in the AChE expression. Since the embryos exposed to GO showed a reduction in overall length, they were submitted to confocal microscopy and their muscle tissue configuration investigated. No changes were observed in the muscle tissue. The results indicated that HA is associated with the toxicity risk modulation by GO and that some compensatory homeostasis mechanisms may be involved in the developmental effects observed in zebrafish.


Assuntos
Grafite/toxicidade , Larva/efeitos dos fármacos , Peixe-Zebra/embriologia , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Ecotoxicologia , Embrião não Mamífero/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Grafite/química , Substâncias Húmicas , Larva/fisiologia , Locomoção/efeitos dos fármacos , Mortalidade , Músculos/citologia , Músculos/efeitos dos fármacos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
16.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370232

RESUMO

Alzheimer's disease (AD) is a multifactorial neurodegenerative disease which is still poorly understood. The drugs currently used against AD, mainly acetylcholinesterase inhibitors (AChEI), are considered clinically insufficient and are responsible for deleterious side effects. AChE is, however, currently receiving renewed interest through the discovery of a chaperone role played in the pathogenesis of AD. But AChE could also serve as an activating protein for pleiotropic prodrugs. Indeed, inhibiting central AChE with brain-penetrating designed carbamates which are able to covalently bind to the enzyme and to concomitantly liberate active metabolites in the brain could constitute a clinically more efficient approach which, additionally, is less likely to cause peripheral side effects. We aim in this article to pave the road of this new avenue with an in vitro and in vivo study of pleiotropic prodrugs targeting both the 5-HT4 receptor and AChE, in order to display a neuroprotective activity associated with a sustained restoration of the cholinergic neurotransmission and without the usual peripheral side effects associated with classic AChEI. This plural activity could bring to AD patients effective, relatively safe, symptomatic and disease-modifying therapeutic benefits.


Assuntos
Acetilcolinesterase/genética , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/farmacologia , Pró-Fármacos/farmacologia , Acetilcolinesterase/química , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Carbamatos/química , Inibidores da Colinesterase/química , Humanos , Ligantes , Pró-Fármacos/química , Receptores 5-HT4 de Serotonina/genética
17.
Parasit Vectors ; 12(1): 396, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399130

RESUMO

BACKGROUND: In the final phase of China's national programme to eliminate malaria by 2020, it is vitally important to monitor the resistance of malaria vectors for developing effective vector control strategies. In 2017 Shanghai declared that it had eliminated malaria; however, the insecticide resistance status of the primary malaria vector Anopheles sinensis remains unknown. METHODS: We examined the pyrethroid and organophosphate resistance of An. sinensis via a bioassay of two populations from the Chongming District of Shanghai. The voltage-gated sodium channel (VGSC) and acetylcholinesterase 1 (ace-1) genes were partially sequenced to examine the association between resistance phenotype and target site genotype. In addition, the geographical distribution, polymorphism and genotype frequencies of insecticide resistance genes were examined using samples collected during routine mosquito surveillance in 2016 and 2017 from Chongming, Songjiang, Jiading and Qingpu Districts. RESULTS: In Chongming District, the An. sinensis population near Dongtan National Nature Reserve showed resistance to pyrethroids, sensitivity to organophosphate, no knockdown resistance (kdr) mutations in the VGSC gene, and a low frequency (1.71%) of the ace-1 119S allele. An An. sinensis population near the Chongming central area (CM-Xinhe population) showed high resistance to pyrethroids and organophosphates and high frequencies of kdr 1014F and 1014C (80.73%) and ace-1 119S (85.98%) alleles. A significant association was detected between the homozygous kdr mutation 1014F/1014F and pyrethroid resistance in the CM-Xinhe population, indicating that the kdr mutation is probably recessive. Eight kdr genotypes with 1014F and 1014C substitutions were detected in the four surveyed districts of Shanghai. TTT and GGC/AGC were the dominant kdr allele and ace-1 genotype, respectively, and were prevalent in most Shanghai An. sinensis populations. CONCLUSIONS: On the basis of our assessment of insecticide resistance gene mutations in Shanghai, we identified a kdr mutation-free population in Chongming Dongtan. However, high frequencies of target-site mutations of insecticide resistance genes were observed in most areas of Shanghai. Bioassays of An. sinensis populations in the central Chongming District indicated the high insecticide resistance status of An. sinensis populations in Shanghai. We accordingly recommend a restriction on insecticide usage and development of effective integrated pest/vector management interventions to support disease control efforts.


Assuntos
Acetilcolinesterase/genética , Anopheles/genética , Resistência a Inseticidas/genética , Inseticidas , Polimorfismo Genético , Canais de Sódio Disparados por Voltagem/genética , Alelos , Animais , Anopheles/enzimologia , Bioensaio , China , Feminino , Genótipo , Geografia , Mosquitos Vetores/genética , Organofosfatos , Piretrinas , Análise de Sequência de DNA
18.
Eur J Pharmacol ; 860: 172529, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31299187

RESUMO

Parasympathetic regulation of urinary bladder contractions primarily involves acetylcholine release and activation of detrusor smooth muscle (DSM) muscarinic acetylcholine (mACh) receptors. Co-release of ATP and activation of DSM purinergic P2X1-receptors may participate as well in some species. Both types of neuromuscular transmission (NMT) are impaired in diabetes, however, which factors may contribute to such impairment remains poorly understood. Here by using rats with streptozotocin(STZ)-induced type I diabetes (8th week after induction) we show that contribution of atropine-sensitive m-cholinergic component to the contractions of urothelium-denuded DSM strips evoked by electric field stimulation (EFS) greatly increased when diabetic bladders presented overt signs of accompanying cystitis. Modeling of hemorrhagic cystitis alone in control rats by cyclophosphamide injection only modestly increased m-cholinergic component of EFS-contractions. However, exposure of DSM strips from control animals to acetylcholinesterase (AChE) inhibitor, neostigmine (1-10 µM) largely reproduced alterations in EFS contractions observed in diabetic DSM complicated by cystitis. Ellman's assay revealed statistically significant 31% decrease of AChE activities in diabetic vs. control DSM. Changes in purinergic contractility of diabetic DSM were consistent with altered P2X1-receptor desensitization and re-sensitization. They could be mimicked by pharmacological inhibition of ATP-degrading ecto-ATPases with ARL 67156 (50 µM), pointing to compromised extracellular ATP clearance as underlying reason. We conclude that decreased AChE activities associated with diabetes and likely cystitis provide complementary factor to the described in literature altered expression of mACh receptor subtypes linked to diabetes as well as to cystitis to produce dramatic modification of cholinergic NMT.


Assuntos
Acetilcolina/metabolismo , Cistite/complicações , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/fisiopatologia , Contração Muscular , Neurotransmissores/metabolismo , Bexiga Urinária/fisiopatologia , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animais de Doenças , Espaço Extracelular/metabolismo , Regulação Enzimológica da Expressão Gênica , Masculino , Ratos , Ratos Wistar
19.
J Surg Res ; 244: 302-311, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31302329

RESUMO

BACKGROUND: Podocyte injury was reported to be involved in the major pathogenesis of ischemia/reperfusion (I/R)-induced ischemic acute renal failure. Our purpose was to study the mechanism of miR-187 improving I/R-induced podocytes injury. MATERIALS AND METHODS: The miR-187 mimics and inhibitor were transfected into the immortalized mouse podocyte (MPC-5) cells, and then transfected cells were subjected to hypoxia/reoxygenation (H/R, 3/3 h) to establish an H/R cell model. To investigate the effects of miR-187 on H/R-induced cell injury, cell viability and apoptosis were measured by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Dual-luciferase report system was used to verify whether miR-187 could directly target acetylcholinesterase (ACHE). The animal ischemia/reperfusion model was established and injected with miR-187 agomir. Kidney tissue sections were subjected to histological examination by hematoxylin and eosin staining to assess the renal injury. Real-time quantitative PCR and western blot were performed to determine gene expressions. RESULTS: The transfection of miR-187 mimics contributed to MPC-cells resistance to H/R-induced cell injury, which was reflected by enhanced cell viability and reduced apoptosis (from 20.05% to 9.43%) in H/R + negative control group. ACHE was confirmed as a target of miR-187, and ACHE siRNA had a similar efficiency to miR-187 mimic. The injection of miR-187 agomir not only effectively protected the kidney from I/R-induced injury, but also reduced the concentrations of serum creatinine. Moreover, nephrin was noticeably increased and desmin was decreased under the effects of agomir. CONCLUSIONS: Our findings indicated that miR-187 improved I/R-induced ischemic acute renal failure through protecting glomerular filtration barrier by blocking the expression of ACHE.


Assuntos
Acetilcolinesterase/genética , Lesão Renal Aguda/prevenção & controle , MicroRNAs/fisiologia , Podócitos/patologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , Sobrevivência Celular , Células Cultivadas , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
20.
PLoS One ; 14(7): e0219598, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31318899

RESUMO

AIMS: Pathophysiology of reflex syncope is not fully understood but a vagal overactivity might be involved in this syncope. Previously, overexpression of muscarinic M2 receptors and acetylcholinesterase was found in particular in the heart and in lymphocytes of rabbits with vagal overactivity as well as in hearts of Sudden Infant Death Syndromes. The aim of this present study was to look at M2 receptor expression in blood of patients with reflex syncope. The second objective was to measure acetylcholinesterase expression in these patients. METHODS AND RESULTS: 136 subjects were enrolled. This monocenter study pooled 45 adults exhibiting recurrent reflex syncope compared with 32 healthy adult volunteers (18-50 years) and 38 children exhibiting reflex syncope requiring hospitalization compared with 21 controls (1-17 years). One blood sample was taken from each subject and blood mRNA expression of M2 receptors was assessed by qRT-PCR. Taking into account the non-symmetric distributions of values in both groups, statistical interferences were assessed using bayesian techniques. A M2 receptor overexpression was observed in adult and pediatric patients compared to controls. The medians [q1;q3] were 0.9 [0.3;1.9] in patients versus 0.2 [0.1;1.0] in controls; the probability that M2 receptor expression was higher in patients than in controls (Pr[patients>controls]) was estimated at 0.99. Acetylcholinesterase expression was also increased 0.7 [0.4;1.6] in patients versus 0.4 [0.2;1.1] in controls; the probability that acetylcholinesterase expression was higher in patients than in controls (Pr[patients>controls]) was estimated at 0.97. Both in adults and children, the expression ratio of M2 receptors over acetylcholinesterase was greater in the patient group compared with the control group. CONCLUSION: M2 receptor overexpression has been detected in the blood of both, adults and children, exhibiting reflex syncope. As in our experimental model, i.e. rabbits with vagal overactivity, acetylcholinesterase overexpression was associated with M2 receptor overexpression. For the first time, biological abnormalities are identified in vagal syncope in which only clinical signs are, so far, taken into account for differential diagnosis and therapeutic management. Further work will be needed to validate potential biomarkers of risk or severity associated with the cholinergic system.


Assuntos
Receptores Muscarínicos/sangue , Síncope Vasovagal/sangue , Acetilcolinesterase/sangue , Acetilcolinesterase/genética , Adulto , Criança , Feminino , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Muscarínicos/genética
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