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1.
J Agric Food Chem ; 72(23): 12967-12974, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814790

RESUMO

Structure-activity relationships of diazinoyl nicotinic insecticides (diazinoyl isomers and 5- or 6-substituted pyrazin-2-oyl analogues) are considered in terms of affinity to the insect nicotinic acetylcholine receptor (nAChR) and insecticidal activity against the imidacloprid-resistant brown planthopper. Among the test compounds, 3-(6-chloropyridin-3-ylmethyl)-2-(pyrazinoyl)iminothiazoline shows the highest potency in nAChR affinity and insecticidal activity. Aplysia californica acetylcholine binding protein (AChBP) mutants (Y55W + Q57R and Y55W + Q57T) are utilized to compare molecular recognition of nicotinic insecticides with diverse pharmacophores. N-nitro- or N-cyanoimine imidacloprid or acetamiprid, respectively, exhibits a high affinity to these AChBP mutants at a similar potency level. Intriguingly, the pyrazin-2-oyl analogue has a higher affinity to AChBP Y55W + Q57R than that to Y55W + Q57T, thereby indicating that pyrazine nitrogen atoms contact Arg57 guanidinium and Trp55 indole NH. Furthermore, nicotine prefers AChBP Y55W + Q57T over Y55W + Q57R, conceivably suggesting that the protonated nicotine is repulsed by Arg57 guanidinium, consistent with its inferior potency to insect nAChR.


Assuntos
Hemípteros , Proteínas de Insetos , Inseticidas , Neonicotinoides , Receptores Nicotínicos , Animais , Inseticidas/química , Inseticidas/farmacologia , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Hemípteros/química , Hemípteros/genética , Hemípteros/efeitos dos fármacos , Hemípteros/metabolismo , Relação Estrutura-Atividade , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Neonicotinoides/química , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Nitrocompostos/química , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Aplysia/química , Aplysia/metabolismo , Aplysia/genética , Nicotina/química , Nicotina/metabolismo , Nicotina/análogos & derivados , Nicotina/farmacologia
2.
Curr Res Insect Sci ; 4: 100066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37559797

RESUMO

Nociception is the sensory perception of noxious chemical stimuli. Repellent behavior to avoid noxious stimuli is indispensable for survival, and this mechanism has been evolutionarily conserved across a wide range of species, from mammals to insects. The transient receptor potential ankyrin 1 (TRPA1) channel is one of the most conserved noxious chemical sensors. Here, we describe the heterologous stable expression of Tribolium castaneum TRPA1 (TcTRPA1) in human embryonic kidney (HEK293) cells. The intracellular Ca2+ influx was measured when two compounds, citronellal and l-menthol, derived from plant essential oils, were applied in vitro using a fluorescence assay. The analysis revealed that citronellal evoked Ca2+ influx dose-dependently for TcTRPA1, whereas l-menthol did not. In combination with our present and previous results of the avoidance-behavioral assay at the organism level, we suggest that TcTRPA1 discriminates between these two toxic compounds, and diversification in the chemical nociception selectivity has occurred in TRPA1 channel among insect taxa.

3.
J Toxicol Sci ; 48(7): 421-428, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37394655

RESUMO

Organophosphate (OP) agents are continuously utilized in large amount throughout the globe for crop protection and public health, thereby creating a potential concern on human health. OP agent as an anticholinesterase also acts on the endocannabinoid (EC)-hydrolases, i.e., fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), to reveal unexpected adverse effects including ADHD-like behaviors in adolescent male rats. The present investigation examines a hypothesis that OP compound inhibiting the EC-hydrolase(s) dysregulates the EC-signaling system, triggering apoptosis in neuronal cells. Ethyl octylphosphonofluoridate (EOPF), as an OP probe, preferably acts on FAAH over MAGL in intact NG108-15 cells. Anandamide (AEA), an endogenous FAAH substrate, is cytotoxic in a concentration-dependent manner, although 2-arachidonoylglycerol, an endogenous MAGL substrate, gives no effect in the concentrations examined here. EOPF pretreatment markedly enhances AEA-induced cytotoxicity. Interestingly, the cannabinoid receptor blocker AM251 diminishes AEA-induced cell death, whereas AM251 does not prevent the cell death in the presence of EOPF. The consistent results are displayed in apoptosis markers evaluation (caspases and mitochondrial membrane potential). Accordingly, FAAH inhibition by EOPF suppresses AEA-metabolism, and accumulated excess AEA overstimulates both the cannabinoid receptor- and mitochondria-mediated apoptotic pathways.


Assuntos
Endocanabinoides , Organofosfatos , Ratos , Masculino , Humanos , Animais , Adolescente , Endocanabinoides/farmacologia , Endocanabinoides/metabolismo , Apoptose
4.
Sci Rep ; 12(1): 15270, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088473

RESUMO

The sensory perception of irritant chemicals results in escape and repellency behavioral patterns in insects. Transient receptor potential channels are cation channels that function as sensor proteins for several types of signals, such as light, sound, temperature, taste, as well as chemical and physical stimuli; among these, the TRPA channel is widely conserved and activated by irritant chemicals. Certain plant-derived essential oils (EOs), produced by secondary metabolism, are mixtures of volatile compounds, which are used as repellents because they contain environmentally sustainable ingredients. Citronellal, which is present in citronella EO from Cymbopogon species, is a potentially viable insect repellent; however, the repellency capability against coleopteran beetles remains limited. We investigated the citronellal-derived repellency behavior for the red flour beetle Tribolium castaneum, in which TcTRPA1 and odorant receptor co-receptor (Orco) expressions were mediated by RNA interference. Area-preference tests showed dose-dependent repellency behavior for citronellal; additionally, both TcTRPA1 and TcOrco double-strand RNA (dsRNA) micro-injection showed clear TcTRPA1 and TcOrco transcript reductions, and only TcTRPA1 dsRNA treatment significantly impaired repellency behavior. The relative expression level of the TcTRPA1 transcripts, evaluated by quantitative reverse-transcription PCR (qRT-PCR), revealed dominant expression in the antennae, indicating the antennae-expressed TcTRPA1-mediated repellency behavior.


Assuntos
Besouros , Cymbopogon , Repelentes de Insetos , Óleos Voláteis , Tribolium , Animais , Repelentes de Insetos/química , Irritantes , Óleos Voláteis/química , RNA de Cadeia Dupla
5.
PLoS One ; 17(1): e0262817, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35045135

RESUMO

Olfaction, one of the most important sensory systems governing insect behavior, is a possible target for pest management. Therefore, in this study, we analyzed the antennal transcriptome of the cowpea beetle, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae), which is a major pest of stored pulses and legumes. The de novo antennal RNA-seq assembly results identified 17 odorant, 2 gustatory, and 10 ionotropic receptors, 1 sensory neuron membrane protein, and 12 odorant-binding and 7 chemosensory proteins. Moreover, differential gene expression analysis of virgin male and female antennal samples followed by qRT-PCR revealed 1 upregulated and 4 downregulated odorant receptors in males. We also performed homology searches using the coding sequences built from previously proposed amino acid sequences derived from genomic data and identified additional chemosensory-related genes.


Assuntos
Antenas de Artrópodes/metabolismo , Besouros/genética , Genes de Insetos , Proteínas de Insetos/genética , RNA-Seq/métodos , Olfato/genética , Transcriptoma/genética , Sequência de Aminoácidos , Animais , Besouros/metabolismo , Regulação para Baixo/genética , Feminino , Masculino , Proteínas de Membrana/genética , Família Multigênica , Proteínas do Tecido Nervoso/genética , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Receptores Ionotrópicos de Glutamato/genética , Receptores Odorantes/genética , Regulação para Cima/genética
6.
J Agric Food Chem ; 69(33): 9551-9556, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34374535

RESUMO

A novel insecticide flupyrimin (FLP) with a trifluoroacetyl pharmacophore acts as an antagonist at the insect nicotinic acetylcholine receptor (nAChR). This investigation examines a hypothesis that the FLP C(O)CF3 moiety is primarily recognized by the ß subunit-face in the ligand-binding pocket (interface between α and ß subunits) of the insect nAChR. Accordingly, we evaluate the atomic interaction between a fluorine atom of FLP and the partnering amino acid side chain on the ß subunit employing a recombinant hybrid nAChR consisting of aphid Mpα2 and rat Rß2 subunits (with a mutation at T77 on the Rß2). The H-donating T77R, T77K, T77N, or T77Q nAChR enhances the FLP binding potency relative to that of the wild-type receptor, whereas the affinity of neonicotinoid imidaclprid (IMI) with a nitroguanidine pharmacophore remains unchanged. These results facilitate the establishment of the unique FLP molecular recognition at the Mpα2/Mpß1 interface structural model, thereby underscoring a distinction in its binding mechanism from IMI.


Assuntos
Afídeos , Inseticidas , Receptores Nicotínicos , Animais , Insetos , Neonicotinoides , Nitrocompostos , Ratos , Receptores Nicotínicos/genética
7.
J Occup Health ; 63(1): e12218, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33779022

RESUMO

OBJECTIVES: The comprehensive detection of environmental chemicals in biospecimens, an indispensable task in exposome research, is advancing. This study aimed to develop an exposomic approach to identify urinary metabolites of organophosphate (OP) pesticides, specifically cadusafos and prothiofos metabolites, as an example chemical group, using an original metabolome dataset generated from animal experiments. METHODS: Urine samples from 73 university students were analyzed using liquid chromatography-high-resolution mass spectrometry. The metabolome data, including the exact masses, retention time (tR ), and tandem mass spectra obtained from the human samples, were compared with the existing reference databases and with our original metabolome dataset for cadusafos and prothiofos, which was produced from mice to whom two doses of these OPs were orally administered. RESULTS: Using the existing databases, one chromatographic peak was annotated as 2,4-dichlorophenol, which could be a prothiofos metabolite. Using our original dataset, one peak was annotated as a putative cadusafos metabolite and three peaks as putative prothiofos metabolites. Of these, all three peaks suggestive of prothiofos metabolites, 2,4-dichlorophenol, 3,4,5-trihydroxy-6-(2,4-dichlorophenoxy) oxane-2-carboxylic acid, and (2,4-dichlorophenyl) hydrogen sulfate were confirmed as authentic compounds by comparing their peak data with both the original dataset and peak data of the standard reagents. The putative cadusafos metabolite was identified as a level C compound (metabolite candidate with limited plausibility). CONCLUSIONS: Our developed method successfully identified prothiofos metabolites that are usually not a target of biomonitoring studies. Our approach is extensively applicable to various environmental contaminants beyond OP pesticides.


Assuntos
Monitoramento Ambiental/métodos , Metabolômica/métodos , Organotiofosfatos/urina , Compostos Organotiofosforados/urina , Praguicidas/urina , Animais , Cromatografia Líquida , Bases de Dados Factuais , Humanos , Metaboloma , Camundongos , Exposição Ocupacional/análise , Valores de Referência , Espectrometria de Massas em Tandem
8.
Pest Manag Sci ; 77(3): 1422-1427, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33128491

RESUMO

BACKGROUND: Among insects, beetles are one of the most destructive pests of agricultural and stored products. Researchers have been investigating alternatives to pesticides for more sustainable pest management. Here, we focused on insect transient receptor potential (TRP) channel-targeted repellency. Among transient receptor potential melastatin (TRPM) channels, mammalian TRPM8 is activated by menthol and its derivatives, but few previous studies have reported on whether the insect TRPM channel is activated by chemical compounds. Here, we investigated whether the TRPM channel (TcTRPM) of the red flour beetle Tribolium castaneum (Herbst), a major stored-products pest, mediated the repellent behavior of l-menthol and its derivatives. RESULTS: We initially investigated the repellent activity of l-menthol and menthoxypropanediol (MPD) against T. castaneum. The laboratory bioassay revealed that the repellent activities of l-menthol and MPD were dose dependent. RNA interference was used for transcriptional knockdown of TcTRPM and revealed that a reduced transcript level resulted in a significant decrease in l-menthol and MPD repellent activities. However, no significant decrease was observed for N,N-diethyl-3-methylbenzamide (DEET) repellency. The most abundant TcTRPM transcripts were observed in the antennae. However, antennae-plucked beetles maintained their repellent behavior with l-menthol. CONCLUSION: The repellent activities of l-menthol and MPD for T. castaneum are mediated by TcTRPM, and it was suggested that the olfactory response is not adequate for avoidance, but that contact repellency might be a more important repellant method. © 2020 Society of Chemical Industry.


Assuntos
Besouros , Repelentes de Insetos , Óleos Voláteis , Canais de Cátion TRPM , Tribolium , Animais , Repelentes de Insetos/farmacologia , Mentol/análogos & derivados , Mentol/farmacologia , Canais de Cátion TRPM/genética
9.
J Antibiot (Tokyo) ; 73(10): 697-701, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32576949

RESUMO

Lascivol was identified as the bitter compound in two Tricholoma species, T. aestuans and T. virgatum, and was previously isolated from the European mushroom T. lascivum. The structure of lascivol was previously solved by X-ray crystallographical analysis but its stereochemistry at C3 remained ambiguous. We thus re-examined the absolute configuration of C3 bearing a hydroxy group using the modified Mosher's method.


Assuntos
Agaricales/química , Glutamatos/isolamento & purificação , Cristalografia por Raios X , Glutamatos/química , Paladar
10.
J Agric Food Chem ; 68(8): 2547-2553, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31995978

RESUMO

Anticholinergic organophosphate (OP) agents act on the diverse serine hydrolases, thereby revealing unexpected biological effects. Epidemiological studies indicate a relationship between the OP exposure and development of attention-deficit/hyperactivity disorder (ADHD)-like symptoms, whereas no plausible mechanism for the OP-induced ADHD has been established. The present investigation employs ethyl octylphosphonofluoridate (EOPF) as an OP-probe, which is an extremely potent inhibitor of endocannabinoid (EC, anandamide and 2-arachidonoylglycerol)-hydrolyzing enzymes: that is, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). An ex vivo experiment shows that EOPF treatment decreases FAAH and MAGL activities and conversely increases EC levels in the rat brain. Subsequently, EOPF (treated intraperitoneally once at 0, 1, 2, or 3 mg/kg) clearly induces ADHD-like behaviors (in elevated plus-maze test) in both Wistar and spontaneously hypertensive rats. The EOPF-induced behaviors are reduced by a concomitant administration of cannabinoid receptor inverse agonist SLV-319. Accordingly, the EC system is a feasible target for OP-caused ADHD-like behaviors in adolescent rats.


Assuntos
Amidoidrolases/antagonistas & inibidores , Transtorno do Deficit de Atenção com Hiperatividade/enzimologia , Encéfalo/enzimologia , Endocanabinoides/metabolismo , Inibidores Enzimáticos/efeitos adversos , Monoacilglicerol Lipases/antagonistas & inibidores , Compostos Organofosforados/efeitos adversos , Amidoidrolases/metabolismo , Animais , Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Masculino , Monoacilglicerol Lipases/metabolismo , Ratos , Ratos Wistar
11.
BMJ Open ; 9(11): e028105, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31722936

RESUMO

PURPOSE: Effects of fetal, perinatal and childhood environment on the health of children at birth and during later life have become a topic of concern. The Aichi regional sub-cohort of the Japan Environment and Children's Study (JECS-A) is an ongoing birth cohort of pregnant women and their children which has been used to provide unique data, as adjunct studies of JECS, on multifaceted potential factors affecting children's health. PARTICIPANTS: The JECS-A is part of the JECS which follows a total of 100 000 pairs of children and their mothers (fathers' participation is optional) across 15 regions in Japan. In JECS-A, of the 8134 pregnant women living in Ichinomiya City and Nagoya City, Japan, a total of 5721 pregnant women and their 5554 children were included. Sociodemographic and psychological data as well as biological specimens were collected from the pregnant women and their spouses (if available) in the cohort during their pregnancy. Information on children included in the JECS-A was collected from their mothers and includes demographic, behavioural, childcare, psychological and psychiatric data. Urine extracted from disposable diapers and anthropometric data were also obtained from the children. FINDINGS TO DATE: A similar distribution trend for age at delivery was confirmed between the pregnant women enrolled in the JECS-A and the national statistics of the relevant areas. However, differences in education level and household income were observed. A total of 5502 children remained in the cohort at 18 months after delivery. Compared with the national statistics, the basic demographics of the children in the cohort represented the population in the study areas. FUTURE PLANS: The enrolled children in the JECS-A will be followed until the age of 13 years. The studies that come from JECS-A will complement JECS and bring novel results with a high level of generalisability.


Assuntos
Saúde da Criança , Exposição Ambiental/efeitos adversos , Pai/estatística & dados numéricos , Mães/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Japão , Masculino , Gravidez , Análise de Regressão , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
12.
Am J Reprod Immunol ; 81(1): e13072, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30430678

RESUMO

PROBLEM: Several studies have reported the increased risk of preterm birth, premature rupture of membranes, and low birth weight in patients with recurrent pregnancy loss (RPL). There have been a limited number of large population-based studies examining adverse pregnancy and perinatal outcome after RPL. Multiple-imputed analyses (MIA) adjusting for biases due to missing data is also lacking. METHOD OF STUDY: A nationwide birth cohort study known as the "Japan Environment and Children's Study (JECS)" was conducted by the Ministry of the Environment. The subjects consisted of 104 102 registered children (including fetuses or embryos). RESULTS: No increased risk of a congenital anomaly, aneuploidy, neonatal asphyxia, or a small for date infant was observed among the children from women with a history of RPL. A novel increased risk of placental adhesion and uterine infection was found. The adjusted ORs using MIA in women with three or more PL were 1.76 (95% CI, 1.04-2.96) for a stillbirth, 1.68 (1.12-2.52) for a pregnancy loss, 2.53 (1.17-5.47) for placental adhesion, 1.87 (1.37-2.55) and 1.60 (.99-2.57) for mild and severe hypertensive disorders of pregnancy, respectively, 1.94 (1.06-3.55) for uterine infection, 1.28 (1.11-1.47) for caesarean section and .86 (.76-.98) for a male infant. CONCLUSION: MIA better quantified the risk, which could encourage women who might hesitate to attempt a subsequent pregnancy.


Assuntos
Aborto Habitual/epidemiologia , Resultado da Gravidez/epidemiologia , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Japão/epidemiologia , Masculino , Computação Matemática , Morte Perinatal , Gravidez , Pontuação de Propensão
13.
Toxicol Lett ; 285: 27-33, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29292090

RESUMO

Fenitrothion (FNT) is used worldwide in agricultural and public health settings. Spermatogenesis is a toxicological target of FNT under high-dose exposure. Although anti-androgenic action is postulated to be the mechanism associated with this toxicity, few studies have examined histopathology of androgen-dependent male accessory sex organs. The present study aimed to reveal the effects of FNT on the accessory organs of rats exhibiting spermatotoxicity in the absence of testicular histopathological changes. Furthermore, a possible novel molecular target was clarified. Male Wistar rats were orally administered 5 or 10 mg/kg FNT or its major metabolite 3-methyl-4-nitrophenol (MNP), or vehicle only, 4 days per week for 9 weeks. Then the epididymis, prostate, and seminal vesicles were collected. FNT and MNP did not show anti-androgenic effects but FNT induced cytoplasmic vacuolation in the epithelial cells of epididymal ducts and hyperplasia of mucosal folds/epithelial papillomatosis in seminal vesicles. FNT and MNP induced epididymal phospholipidosis, which was presumably caused by inhibition of epididymal secreted phospholipase A2 (sPLA2). Percentages of morphologically normal sperm and immature sperm were significantly predicted from both epididymal sPLA2 and phospholipid levels and from epididymal sPLA2, respectively. These results suggest that epididymal phospholipidosis plays an important role in FNT-induced spermatotoxicity. Anti-androgenic actions were not observed.


Assuntos
Epididimo/efeitos dos fármacos , Fenitrotion/toxicidade , Inseticidas/toxicidade , Fosfolipídeos/metabolismo , Espermatogênese/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Epididimo/metabolismo , Epididimo/patologia , Masculino , Fosfolipases A2/metabolismo , Ratos Wistar
14.
J Agric Food Chem ; 65(36): 7865-7873, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28820587

RESUMO

A novel chemotype insecticide flupyrimin (FLP) [N-[(E)-1-(6-chloro-3-pyridinylmethyl)pyridin-2(1H)-ylidene]-2,2,2-trifluoroacetamide], discovered by Meiji Seika Pharma, has unique biological properties, including outstanding potency to imidacloprid (IMI)-resistant rice pests together with superior safety toward pollinators. Intriguingly, FLP acts as a nicotinic antagonist in American cockroach neurons, and [3H]FLP binds to the multiple high-affinity binding components in house fly nicotinic acetylcholine (ACh) receptor (nAChR) preparation. One of the [3H]FLP receptors is identical to the IMI receptor, and the alternative is IMI-insensitive subtype. Furthermore, FLP is favorably safe to rats as predicted by the very low affinity to the rat α4ß2 nAChR. Structure-activity relationships of FLP analogues in terms of receptor potency, featuring the pyridinylidene and trifluoroacetyl pharmacophores, were examined, thereby establishing the FLP molecular recognition at the Aplysia californica ACh-binding protein, a suitable structural surrogate of the insect nAChR. These FLP pharmacophores account for the excellent receptor affinity, accordingly revealing differences in its binding mechanism from IMI.


Assuntos
Inseticidas/química , Inseticidas/farmacologia , Antagonistas Nicotínicos/química , Antagonistas Nicotínicos/farmacologia , Receptores Nicotínicos/química , Animais , Aplysia/efeitos dos fármacos , Aplysia/metabolismo , Sítios de Ligação , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Cinética , Periplaneta/efeitos dos fármacos , Periplaneta/genética , Periplaneta/metabolismo , Ratos , Receptores Nicotínicos/metabolismo , Relação Estrutura-Atividade
15.
Curr Microbiol ; 74(1): 49-54, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27785552

RESUMO

A non-toxigenic mutant of the toxigenic serotype C Clostridium botulinum strain Stockholm (C-St), C-N71, does not produce the botulinum neurotoxin (BoNT). However, the original strain C-St produces botulinum toxin complex, in which BoNT is associated with non-toxic non-hemagglutinin (NTNHA) and three hemagglutinin proteins (HA-70, HA-33, and HA-17). Therefore, in this study, we aimed to elucidate the effects of bont gene knockout on the formation of the "toxin complex." Nucleotide sequence analysis revealed that a premature stop codon was introduced in the bont gene, whereas other genes were not affected by this mutation. Moreover, we successfully purified the "toxin complex" produced by C-N71. The "toxin complex" was identified as a mixture of NTNHA/HA-70/HA-17/HA-33 complexes with intact NTNHA or C-terminally truncated NTNHA, without BoNT. These results indicated that knockout of the bont gene does not affect the formation of the "toxin complex." Since the botulinum toxin complex has been shown to play an important role in oral toxin transport in the human and animal body, a non-neurotoxic "toxin complex" of C-N71 may be valuable for the development of an oral drug delivery system.


Assuntos
Proteínas de Bactérias/genética , Toxinas Botulínicas/genética , Clostridium botulinum/genética , Deleção de Sequência , Proteínas de Bactérias/metabolismo , Toxinas Botulínicas/metabolismo , Botulismo/microbiologia , Clostridium botulinum/classificação , Clostridium botulinum/metabolismo , Humanos
16.
Microbiol Res ; 193: 20-29, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27825483

RESUMO

Botulinolysin (BLY) is a toxin produced by Clostridium botulinum that belongs to a group of thiol-activated hemolysins. In this study, a protein exhibiting hemolytic activity was purified from the culture supernatant of C. botulinum serotype D strain 4947. The purified protein displayed a single band by sodium dodecyl sulfate polyacrylamide gel electrophoresis with a molecular mass of 55kDa, and its N-terminal and internal amino acid sequences exhibited high similarity to a group of thiol-activated hemolysins produced by gram-positive bacteria. Thus, the purified protein was identified as the BLY. Using the nucleotide sequences of previously cloned genes for hemolysins, two types of genes encoding BLY-like proteins were cloned unexpectedly. Molecular modeling analysis indicated that the products of both genes displayed very similar structures, despite the low sequence similarity. In silico screening revealed a specific duplication of the hemolysin gene restricted to serotypes C and D of C. botulinum and their related species among thiol-activated hemolysin-producing bacteria. Our findings provide important insights into the genetic characteristics of pathogenic bacteria.


Assuntos
Clostridium botulinum/genética , Duplicação Gênica , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/isolamento & purificação , Hemolíticos/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Clostridium botulinum/classificação , Análise por Conglomerados , Eletroforese em Gel de Poliacrilamida , Proteínas Hemolisinas/química , Proteínas Hemolisinas/metabolismo , Hemolíticos/química , Hemolíticos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Filogenia , Conformação Proteica , Análise de Sequência de DNA , Homologia de Sequência , Sorogrupo
17.
Toxicol Appl Pharmacol ; 279(3): 331-337, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24998969

RESUMO

Organophosphate (OP) compounds as anticholinesterase agents may secondarily act on diverse serine hydrolase targets, revealing unfavorable physiological effects including male reproductive toxicity. The present investigation proposes that fenitrothion (FNT, a major OP compound) acts on the endocannabinoid signaling system in male reproductive organs, thereby leading to spermatotoxicity (sperm deformity, underdevelopment, and reduced motility) in rats. FNT oxon (bioactive metabolite of FNT) preferentially inhibited the fatty acid amide hydrolase (FAAH), an endocannabinoid anandamide (AEA) hydrolase, in the rat cellular membrane preparation from the testis in vitro. Subsequently, male Wistar rats were treated orally with 5 or 10mg/kg FNT for 9 weeks and the subchronic exposure unambiguously deteriorated sperm motility and morphology. The activity-based protein profiling analysis with a phosphonofluoridate fluorescent probe revealed that FAAH was selectively inhibited among the FNT-treated cellular membrane proteome in testis. Intriguingly, testicular AEA (endogenous substrate of FAAH) levels were elevated along with the FAAH inhibition caused by the subchronic exposure. More importantly, linear regression analyses for the FNT-elicited spermatotoxicity reveal a good correlation between the testicular FAAH activity and morphological indices or sperm motility. Accordingly, the present study proposes that the FNT-elicited spermatotoxicity appears to be related to inhibition of FAAH leading to overstimulation of the endocannabinoid signaling system, which plays crucial roles in spermatogenesis and sperm motility acquirement.


Assuntos
Endocanabinoides/fisiologia , Fenitrotion/toxicidade , Inseticidas/toxicidade , Espermatozoides/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Amidoidrolases/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Epididimo/citologia , Epididimo/efeitos dos fármacos , Hormônios Esteroides Gonadais/metabolismo , Masculino , Espectrometria de Massas , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/psicologia , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura , Testículo/efeitos dos fármacos , Testículo/enzimologia , Testículo/metabolismo
18.
Toxicol Lett ; 225(1): 153-7, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24361246

RESUMO

Diverse serine hydrolases including endocannabinoid metabolizing enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) have been suggested as secondary targets for organophosphate (OP) agents to exert adverse toxic effects such as lipid homeostasis disruption. The goal of this investigation is to verify that a major OP insecticide fenitrothion (FNT) induces plasma hypertriglyceridemia through the inhibition of FAAH and/or MAGL in comparison with that elicited by isopropyl dodecylfluorophosphonate (IDFP), a potent FAAH/MAGL inhibitor. Fasted mice were treated intraperitoneally with FNT or IDFP and were subsequently sacrificed for evaluations of plasma triglyceride (TG) levels and liver FAAH/MAGL activities. Plasma TG levels were significantly enhanced by the FNT or IDFP treatment (1.7- or 4.8-fold, respectively) compared with that of vehicle control. The IDFP exposure reduced the liver FAAH and MAGL activities, whereas the FNT exposure led to the preferential FAAH inhibition. The brain acetylcholinesterase was almost unaffected by the FNT or IDFP treatment, thus leading to no neurotoxic sign. Intriguingly, the TG elevations were averted by concomitant administration with the cannabinoid receptor antagonist AM251. The present findings suggest that OP agents induce plasma hypertriglyceridemia in mouse through single or dual inhibition of FAAH or/and MAGL, apparently leading to overstimulation of cannabinoid signal regulating energy metabolism.


Assuntos
Amidoidrolases/antagonistas & inibidores , Endocanabinoides/metabolismo , Inibidores Enzimáticos/toxicidade , Fenitrotion/toxicidade , Hipertrigliceridemia/induzido quimicamente , Inseticidas/toxicidade , Fígado/efeitos dos fármacos , Monoacilglicerol Lipases/antagonistas & inibidores , Triglicerídeos/sangue , Acetilcolinesterase/metabolismo , Amidoidrolases/metabolismo , Animais , Biomarcadores/sangue , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Antagonistas de Receptores de Canabinoides/farmacologia , Relação Dose-Resposta a Droga , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/metabolismo , Hidrólise , Hipertrigliceridemia/sangue , Hipertrigliceridemia/enzimologia , Hipertrigliceridemia/prevenção & controle , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Monoacilglicerol Lipases/metabolismo , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptores de Canabinoides/efeitos dos fármacos , Receptores de Canabinoides/metabolismo , Regulação para Cima
19.
J Agric Food Chem ; 61(41): 9961-5, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24044584

RESUMO

Organophosphate (OP) insecticides as an anticholinesterase also act on the diverse serine hydrolase targets, thereby revealing secondary or unexpected toxic effects including male reproductive toxicity. The present investigation detects a possible target molecule(s) for OP-induced spermatotoxicity (sperm deformity, underdevelopment, and reduced motility) from a chemical standpoint. The activity-based protein profiling (ABPP) approach with a phosphonofluoridate fluorescent probe pinpointed the molecular target for fenitrothion (FNT, a major OP insecticide) oxon (bioactive metabolite of FNT) in the mouse testicular membrane proteome, i.e., FNT oxon phosphorylates the fatty acid amide hydrolase (FAAH), which plays pivotal roles in spermatogenesis and sperm motility acquirement. Subsequently, mice were treated orally with vehicle or FNT for 10 days, and FAAH activity in testis or epididymis cauda was markedly reduced by the subacute exposure. ABPP analysis revealed that FAAH was selectively inhibited among the FNT-treated testicular membrane proteome. Accordingly, FAAH is a potential target for OP-elicited spermatotoxicity.


Assuntos
Fenitrotion/toxicidade , Inseticidas/toxicidade , Compostos Organofosforados/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Epididimo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/citologia
20.
Bioorg Med Chem Lett ; 23(19): 5434-6, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23953192

RESUMO

The present report describes for the first time that anticholinesterase type insecticides specifically inhibit the fatty acid amide hydrolase and/or monoacylglycerol lipase, as secondary target(s), in the murine male reproductive system (testis and epididymis cauda), thereby presumably being involved with spermatotoxicity such as deformity, underdevelopment, and reduced motility.


Assuntos
Amidoidrolases/antagonistas & inibidores , Inibidores da Colinesterase/farmacologia , Inseticidas/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Inibidores da Colinesterase/química , Ativação Enzimática/efeitos dos fármacos , Doenças dos Genitais Masculinos/induzido quimicamente , Inseticidas/química , Masculino , Camundongos , Estrutura Molecular
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