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1.
Adv Ther ; 37(8): 3537-3550, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32564268

RESUMO

INTRODUCTION: Dabigatran is a direct oral anticoagulant (DOAC) used for the treatment of several thrombotic conditions. To date, very few pharmacogenetic studies on dabigatran were published. We aimed to investigate the influence of 59 polymorphisms in 15 genes (including CES1, UGT and CYP that encode enzymes and ABCB1 and SLC that encode transporters), concomitant treatment with pantoprazole and demographic characteristics (including sex or race) on dabigatran pharmacokinetics and safety. METHODS: This was a candidate gene pharmacogenetic study. The study population comprised 107 volunteers enrolled in two dabigatran bioequivalence clinical trials; they were genotyped with a ThermoFisher QuantStudio 12K Flex OpenArray instrument. SPSS software v.21 was used for statistical analysis. RESULTS: Women showed a higher exposure to dabigatran compared to men. The concomitant treatment with pantoprazole was associated with a decreased exposure to the drug. CYP2D6 poor metabolizers (PMs) were related to lower clearance (Cl/F) (p = 0.049) and a tendency was observed towards higher area under the curve (AUC), maximum concentration (Cmax) and to lower volume of distribution (Vd/F) (p < 0.10). SLC22A1 haplotype was related to pharmacokinetic variability (p < 0.05). The remaining genes (including CYP, UGT1A1 and ABCB1) had no effect on dabigatran pharmacokinetics (p > 0.10). Women showed more adverse drug reactions (ADR) compared to men (0.40 ± 0.68 vs 0.15 ± 0.41 ADR per person, p = 0.03) and SLC22A1 mutant haplotype was related to a lower risk of nausea (p = 0.02). CONCLUSION: Sex, concomitant use of pantoprazole and SLC22A1, CYP2D6 and CYP3A5 polymorphism had an effect on dabigatran pharmacokinetics and safety. Previously published pharmacogenetic predictors, namely CES1 or ABCB1 polymorphisms, had no effect on pharmacokinetics and safety. This study is of interest as it increases the scarce pharmacogenetic information on dabigatran.


Assuntos
Antitrombinas/uso terapêutico , Dabigatrana/farmacocinética , Genótipo , Pantoprazol/farmacocinética , Farmacogenética , Polimorfismo Genético , Trombose/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Adolescente , Adulto , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Antitrombinas/farmacocinética , Área Sob a Curva , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Citocromo P-450 CYP2D6/efeitos dos fármacos , Citocromo P-450 CYP3A/efeitos dos fármacos , Dabigatrana/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transportador 1 de Cátions Orgânicos/efeitos dos fármacos , Pantoprazol/uso terapêutico , Inibidores da Bomba de Prótons/farmacocinética , Inibidores da Bomba de Prótons/uso terapêutico , Fatores Sexuais , Espanha , Adulto Jovem
2.
Exp Neurol ; 324: 113128, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31759899

RESUMO

MicroRNA-592 (miR-592) has been reported to play a significant role in mediating neuronal activity, but its possible link with Alzheimer's disease (AD) remains unclear. We aimed to explore the mechanism of miR-592 in oxidative stress (OS) injury of astrocytes (ASTs) from AD rat models induced by D-galactose or Aß25-35 injection. Bioinformatics website and dual-luciferase reporter gene assay clarified the binding affinity between miR-592 and KIAA0319. KIAA0319 was identified as a target gene of miR-592. The mechanism of miR-592, KIAA0319 and the Keap1/Nrf2/ARE signaling pathway in AD was examined after transducing miR-592 mimic, miR-592 inhibitor and siRNA-KIAA0319 into ASTs to query cell viability, OS injury and reactive oxygen species (ROS). The rat models of AD Exhibited highly expressed miR-592 and poorly expressed KIAA0319. Furthermore, inhibition of miR-592 diminished C-Keap1 expression and enhanced N-Nrf2 and NQO1 expression, thus promoting cell viability and reducing OS injury of ASTs. Taken together, these findings suggested that the downregulation of miR-592 inhibited OS injury of ASTs in rat models of AD by up-regulating KIAA0319 through the activation of the Keap1/Nrf2/ARE signaling pathway.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Moléculas de Adesão Celular/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/efeitos dos fármacos , MicroRNAs/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides , Animais , Biologia Computacional , Galactose , Masculino , Aprendizagem em Labirinto , Fragmentos de Peptídeos , Ratos , Ratos Sprague-Dawley
3.
Eur J Med Chem ; 175: 2-19, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31055149

RESUMO

2-(piperazin-1-yl)N-(1H-pyrazolo[3,4-b]pyridin-3-yl)acetamides are described as a new class of selective and potent acetylcholinesterase (AChE) inhibitors and amyloid ß aggregation inhibitors. Formation of synthesized compounds (P1P9) was justified via H1 NMR, C13 NMR, mass spectra and single crystal X-Ray diffraction study. All compounds were evaluated for their acetylcholinesterase and butyrylcholinesterase inhibitory activity, inhibition of self-mediated Aß aggregation and Cu(II)-mediated Aß aggregation. Also, docking study carried out was in concordance with in vitro results. The most potent molecule amongst the derivatives exhibited excellent anti-AChE activity (IC50 = 4.8 nM). Kinetic study of P3 suggested it to be a mixed type inhibitor. In vitro study revealed that all the compounds are capable of inhibiting self-induced ß-amyloid (Aß) aggregation with the highest inhibition percentage to be 81.65%. Potency of P1 and P3 to inhibit self-induced Aß1-42 aggregation was ascertained by TEM analysis. Compounds were also evaluated for their Aß disaggregation, antioxidation, metal-chelation activity.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Pirazóis/química , Pirazóis/uso terapêutico , Piridinas/química , Piridinas/uso terapêutico , Acetilcolinesterase/efeitos dos fármacos , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/ultraestrutura , Antioxidantes/farmacologia , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Quelantes/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Cobre/química , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Concentração Inibidora 50 , Microscopia Eletrônica de Transmissão , Simulação de Acoplamento Molecular , Pirazóis/síntese química , Piridinas/síntese química , Espectrometria de Fluorescência
4.
Folia Neuropathol ; 56(3): 179-186, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30509039

RESUMO

The present investigation evaluates the protective effect of vorinostat on neuronal cells in the traumatic brain injury (TBI) and also postulates the possible mechanism of its action. Marmarou's weight-drop model was used to induce the TBI. Further, animals were treated with vorinostat 100 mg/kg intraperitoneally 30 min before the TBI induction. Neurological score and brain water content were determined in all the groups and thereafter oxidative stress parameters and adenosine triphosphate (ATP) content were determined in the neuronal tissues of TBI mice. Western blot assay and reverse transcription polymerase chain reaction (RT-PCR) was performed for the determination of the expression of several proteins in the neuronal tissues. Moreover, immunohistochemical staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was also done on the neuronal tissues of TBI mice. Data of the study reveal that treatment with vorinostat significantly reduces the altered level of grip test scores and water content in the brain of traumatic injured mice. Moreover, the altered level of oxidative stress parameters, translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and ATP content was attenuated by treating TBI mice with vorinostat. Also treatment with vorinostat ameliorates the altered expression of p-Akt, NF-B, iNOS and caspase by the western blot assay in the neuronal tissue of TBI mice and mRNA level of HO-1 and NQO-1 significantly enhanced in vorinostat compared to the negative control group. Furthermore, the TUNEL assay also reveals that the apoptosis of neuronal cells was significantly (p < 0.01) reduced in the vorinostat-treated group compared to the negative control group. The present study concludes that vorinostat protects the neuronal injury in TBI mice by reducing the altered level of oxidative stress and inflammatory response.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Encéfalo/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vorinostat/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas Traumáticas/metabolismo , Hidrolases de Éster Carboxílico/biossíntese , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos
5.
Toxicology ; 410: 73-82, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30176330

RESUMO

Some effects of organophosphorus compounds (OPs) esters cannot be explained by action on currently recognized targets acetylcholinesterase or neuropathy target esterase (NTE). In previous studies, in membrane chicken brain fractions, four components (EPα, EPß, EPγ and EPδ) of phenyl valerate esterase activity (PVase) had been kinetically discriminated combining data of several inhibitors (paraoxon, mipafox, PMSF). EPγ is belonging to NTE. The relationship of PVase components and acetylcholine-hydrolyzing activity (cholinesterase activity) is studied herein. Only EPα PVase activity showed inhibition in the presence of acetylthiocholine, similarly to a non-competitive model. EPα is highly sensitive to mipafox and paraoxon, but is resistant to PMSF, and is spontaneously reactivated when inhibited with paraoxon. In this papers we shows that cholinesterase activities showed inhibition kinetic by PV, which does not fit with a competitive inhibition model when tested for the same experimental conditions used to discriminate the PVase components. Four enzymatic components (CP1, CP2, CP3 and CP4) were discriminated in cholinesterase activity in the membrane fraction according to their sensitivity to irreversible inhibitors mipafox, paraoxon, PMSF and iso-OMPA. Components CP1 and CP2 could be related to EPα as they showed interactions between substrates and similar inhibitory kinetic properties to the tested inhibitors.


Assuntos
Encéfalo/enzimologia , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Galinhas/metabolismo , Inibidores da Colinesterase/farmacologia , Colinesterases/efeitos dos fármacos , Compostos Organofosforados/farmacologia , Animais , Ligação Competitiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cinética , Membranas/efeitos dos fármacos , Membranas/enzimologia
6.
Toxicology ; 410: 10-15, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30172647

RESUMO

Genetics likely play a role in various responses to nerve agent (NA) exposure, as genetic background plays an important role in behavioral, neurological, and physiological responses. This study uses different mouse strains to identify if mouse strain differences in sarin exposure exist. In Experiment 1, basal levels of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CE) were measured in different strains of naïve mice to account for potential pharmacokinetic determinants of individual differences. In Experiment 2, median lethal dose (MLD) levels were estimated in 8 inbred mouse strains following subcutaneous (s.c.) administration of sarin. Few strain or sex differences in esterase activity levels were observed, with the exception of erythrocyte AChE activity in the C57BL/6J strain. Both sex and strain differences in toxicity were observed, with the most resistant strains being the BALB/cByJ and FVB/NJ strains and the most sensitive strain being the DBA/2J strain. These findings can be expanded to explore pathways involved in NA response, which may provide an avenue to develop therapeutics for preventing and treating the damaging effects of NA exposure.


Assuntos
Substâncias para a Guerra Química/toxicidade , Esterases/efeitos dos fármacos , Esterases/metabolismo , Camundongos Endogâmicos , Agentes Neurotóxicos/toxicidade , Sarina/toxicidade , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/efeitos dos fármacos , Butirilcolinesterase/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Inibidores da Colinesterase/toxicidade , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Feminino , Injeções Subcutâneas , Dose Letal Mediana , Masculino , Camundongos , Especificidade da Espécie
7.
Appl Microbiol Biotechnol ; 101(10): 4201-4213, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28224194

RESUMO

Upregulation of glycolysis and the pentose phosphate pathway (PPP) is a major characteristic of the metabolic reprogramming of cancer and provides cancer cells with energy and vital metabolites to support their rapid proliferation. Targeting glycolysis and the PPP has emerged as a promising antitumor therapeutic strategy. Marine natural products are attractive sources for anticancer therapeutics, as evidenced by the antitumor drug Yondelis. Mycoepoxydiene (MED) is a natural product isolated from a marine fungus that has shown promising inhibitory efficacy against HeLa cells in vitro. We used a proteomic approach with two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry to explore the cellular targets of MED and to unravel the molecular mechanisms underlying the antitumor activity of MED in HeLa cells. Our proteomic data showed that triosephosphate isomerase (TPI) and 6-phosphogluconolactonase (PGLS), which participate in glycolysis and the PPP, respectively, were significantly downregulated by MED treatment. Functional studies revealed that the expression levels of several other enzymes involved in glycolysis and the PPP, including hexokinase 2 (HK2), phosphofructokinase 1 (PFKM), aldolase A (ALDOA), enolase 1 (ENO1), lactate dehydrogenase A (LDHA), and glucose-6-phosphate dehydrogenase (G6PD), were also reduced in a dose-dependent manner. Moreover, the LDHA and G6PD enzymatic activities in HeLa cells were inhibited by MED, and overexpression of these downregulated enzymes rescued HeLa cells from the growth inhibition induced by MED. Our data suggest that MED suppresses HeLa cell growth by inhibiting glycolysis and the PPP, which provides a mechanistic basis for the development of new therapeutics against cervical cancer.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/farmacologia , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Pironas/farmacologia , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/genética , Ciclo Celular/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Glucose/metabolismo , Glicólise/genética , Células HeLa , Hexoquinase/efeitos dos fármacos , Hexoquinase/genética , Humanos , Oxirredução , Via de Pentose Fosfato/genética , Proteômica , Triose-Fosfato Isomerase/efeitos dos fármacos , Triose-Fosfato Isomerase/genética
8.
Acta Trop ; 163: 167-78, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27443607

RESUMO

The current study investigated the toxic effect of the leaf extract compound andrographolide from Andrographis paniculata (Burm.f) against the dengue vector Ae. aegypti. GC-MS analysis revealed that andrographolide was recognized as the major chemical constituent with the prominent peak area compared with other compounds. All isolated toxic compounds were purified and confirmed through RP-HPLC against chemical standards. The larvicidal assays established at 25ppm of bioactive compound against the treated instars of Ae. Aegypti showed prominent mortality compared to other treated concentrations. The percent mortality of larvae was directly proportional to concentration. The lethal concentration (LC50) was observed at 12ppm treatment concentration. The bioactive andrographolide considerably reduced the detoxifying enzyme regulations of α- and ß- carboxylesterases. In contrast, the levels of GST and CYP450 significantly increase in a dose dependent manner. The andrographolide also showed strong oviposition deterrence effects at the sub-lethal dose of 12ppm. Similarly, the mean number of eggs were also significantly reduced in a dose dependent manner. At the concentration of 12ppm the effective percentage of repellency was greater than 90% with a protection time of 15-210min, compared with control. The histopathology study displayed that larvae treated with bioactive andrographolide had cytopathic effects in the midgut epithelium compared with the control. The present study established that bioactive andrographolide served as a potential useful for dengue vector management.


Assuntos
Aedes/efeitos dos fármacos , Andrographis , Dengue/prevenção & controle , Diterpenos/farmacologia , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Feminino , Glutationa Transferase/efeitos dos fármacos , Espectrometria de Massas , Controle de Mosquitos , Oviposição/efeitos dos fármacos , Folhas de Planta
9.
Artigo em Inglês | MEDLINE | ID: mdl-25151331

RESUMO

A sensitive, accurate and rugged UHPLC-MS/MS method was developed and validated for the quantitation of Epothilone D (EpoD), a microtubule stabilizer in development for treatment of Alzeimer's disease, in rat plasma. The ester group in EpoD can be hydrolyzed by esterases in blood or plasma, which creates a stability concern for the bioanalysis of EpoD. Species differences in the stability of EpoD in plasma were observed. Carboxylesterases were identified as the likely esterases responsible for the hydrolysis of EpoD in plasma ex vivo, and the cause of the species different stability. Phenylmethanesulfonyl fluoride, a carboxylesterase inhibitor, was used to stabilize EpoD in rat blood during sample collection, processing, and storage. A systematic method screening and optimization strategy was used to improve the assay sensitivity and minimize potential bioanalytical risks. The stabilized plasma samples were extracted by liquid-liquid extraction. Chromatographic separation was achieved on an Acquity UPLC BEH Phenyl column with a gradient elution. EpoD and its stable isotope labeled internal standards were detected by positive ion electrospray tandem mass spectrometry. The standard curve, which ranged from 0.100 to 100ng/mL was fitted to a 1/x(2) weighted linear regression model. The intra-assay precision was within ±3.6% CV and inter-assay precision was within ±4.2% CV. The assay accuracy was within ±8.3% of the nominal values. Assay recovery of EpoD was high (∼90%) and matrix effect was minimal (1.02-1.05). EpoD was stable in stabilized rat plasma for at least 30h at room temperature, 180 days at -20°C, and following three freeze-thaw cycles. The validated method was successfully applied to sample analysis in toxicology studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Epotilonas/sangue , Epotilonas/química , Fluoreto de Fenilmetilsulfonil/química , Espectrometria de Massas em Tandem/métodos , Animais , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Estabilidade de Medicamentos , Epotilonas/farmacocinética , Feminino , Modelos Lineares , Fluoreto de Fenilmetilsulfonil/farmacologia , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Food Sci Technol Int ; 20(4): 287-98, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23751545

RESUMO

The effect of postharvest 1-methylcyclopropene and/or cold storage application on texture quality parameters during storage was determined. The changes in fruit quality (including weight loss, firmness, total soluble solids content, and ethylene production), cell wall material (including water-soluble fraction, ethylenediaminetetraacetic acid-soluble fraction, Na2CO3-soluble fraction, 4% KOH-soluble fraction, and 14% KOH-soluble fraction), and cell wall hydrolase activities (including polygalacturonase, endo-1,4-beta-D-glucanase, pectinesterase, alpha-L-arabinofuranosidase, and beta-galactosidase) were periodically measured up to 25 days after postharvest treatments. The application of cold storage reduced weight loss, ethylene production, and delayed ripening of blueberry fruit. The inhibition of senescence was associated with suppressed increase in cell wall hydrolase activities and retarded solubilization of pectins and hemicelluloses. Furthermore, no obvious differences in firmness, weight loss, ethylene production, and cell wall hydrolase activities between fruits with or without 1-methylcyclopropene application were observed, while significant lower levels of the detected parameters were found in cold storage fruit compared with fruit stored in room temperature. Thus, cold storage can be viewed as an effective means to extend the shelf life of blueberry fruit.


Assuntos
Mirtilos Azuis (Planta)/química , Parede Celular/química , Temperatura Baixa , Ciclopropanos/farmacologia , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Análise de Variância , Mirtilos Azuis (Planta)/efeitos dos fármacos , Hidrolases de Éster Carboxílico/análise , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Etilenos/análise , Hidrolases/análise , Hidrolases/efeitos dos fármacos , Pectinas/análise , Poligalacturonase/análise , Poligalacturonase/efeitos dos fármacos , Polissacarídeos/análise , Fatores de Tempo
11.
Food Sci Technol Int ; 20(4): 309-17, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23744122

RESUMO

Papaya fruits (Carica papaya L. cv 'Sui you 2') harvested with < 5% yellow surface at the blossom end were fumigated with 60 microL/L of nitric oxide for 3 h and then stored at 20 degrees C with 85% relative humility for 20 days. The effects of nitric oxide treatment on ethylene production rate, the activities of cell wall softening related enzymes including polygalacturonase, pectin methyl esterase, pectate lyase and cellulase and the levels of hormones including indole acetic acid, abscisic acid, gibberellin and zeatin riboside were examined. The results showed that papaya fruits treated with nitric oxide had a significantly lower rate of ethylene production and a lesser loss of firmness during storage. A decrease in polygalacturonase, pectin methyl esterase, pectate lyase and cellulase activities was observed in nitric oxide treated fruit. In addition, the contents of indole acetic acid, abscisic acid and zeatin riboside were reduced in nitric oxide treated fruit, but no significant reduction in the level of gibberellin was found. These results indicate that nitric oxide treatment can effectively delay the softening and ripening of papaya fruit, likely via the regulation of cell wall softening related enzymes and certain hormones.


Assuntos
Carica/efeitos dos fármacos , Carica/enzimologia , Parede Celular/efeitos dos fármacos , Armazenamento de Alimentos/métodos , Óxido Nítrico/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/análise , Ácido Abscísico/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Celulase/efeitos dos fármacos , Celulase/metabolismo , Etilenos/metabolismo , Sequestradores de Radicais Livres/farmacologia , Giberelinas/análise , Giberelinas/metabolismo , Ácidos Indolacéticos/análise , Ácidos Indolacéticos/metabolismo , Isopenteniladenosina/análogos & derivados , Isopenteniladenosina/análise , Isopenteniladenosina/metabolismo , Reguladores de Crescimento de Plantas/análise , Poligalacturonase/efeitos dos fármacos , Poligalacturonase/metabolismo , Polissacarídeo-Liases/efeitos dos fármacos , Polissacarídeo-Liases/metabolismo
12.
Appl Biochem Biotechnol ; 170(3): 654-75, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23604968

RESUMO

Two genes, cut1 and cut2, of Thermobifida fusca NRRL B-8184 with cutin-hydrolyzing activity were cloned and expressed in Escherichia coli BL21 (DE3) separately. Enhanced expression was achieved after screening of six different media, optimization of the culture conditions and medium components. Among the screened media, modified Terrific Broth was found to be the best for maximum production of recombinant cutinases in E. coli BL21 (DE3). Under optimal conditions, the production of recombinant Cut1 and Cut2 (cutinases) were found to be 318±0.73 and 316±0.90 U/ml, respectively. The production of recombinant cutinases was increased by 11-fold as compared with T. fusca NRRL B-8184 wild-type strain. Both the recombinant cutinases were purified to homogeneity. They were found to be thermostable, organic solvent, and surfactant tolerant. Both the cutinase were active in a broad range of temperature (40-80 °C) and pH (6.8-9) with optimum activity at pH 8.0 and 55 °C.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Actinomycetales/enzimologia , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/isolamento & purificação , Clonagem Molecular , Meios de Cultura , Estabilidade Enzimática , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Solventes/farmacologia , Temperatura
13.
Planta ; 236(4): 989-97, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22526505

RESUMO

The physiological and molecular mechanisms leading to the competitive interactions between phosphorus (P) and metal elements are a matter of debate. In this study, we found that P deficiency can alleviate cadmium (Cd) toxicity in Arabidopsis thaliana (Col-0). Under P deficiency (-P), less Cd was accumulated in the plants and the root cell walls, indicating the operation of a P-deficiency-induced Cd exclusion mechanism. However, organic acid efflux was similar under -P+Cd and +Cd treatments, suggesting that organic acid efflux is not responsible for the Cd exclusion. Interestingly, P deficiency significantly decreased cell wall polysaccharides (pectin and hemicellulose) contents and pectin methylesterase activity, and decreased the Cd retained by the extracted root cell wall. Therefore, we conclude that the modification of cell wall composition is responsible for the Cd exclusion of the root under P deficiency.


Assuntos
Arabidopsis/metabolismo , Cádmio/toxicidade , Parede Celular/metabolismo , Fósforo/deficiência , Polissacarídeos/metabolismo , Arabidopsis/química , Arabidopsis/efeitos dos fármacos , Cádmio/análise , Cádmio/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/química , Parede Celular/efeitos dos fármacos , Clorofila/metabolismo , Ácido Cítrico/análise , Ácido Cítrico/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pectinas/análise , Pectinas/metabolismo , Exsudatos de Plantas/química , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Polissacarídeos/análise , Plântula/química , Plântula/efeitos dos fármacos , Plântula/metabolismo , Ácidos Urônicos/análise , Ácidos Urônicos/metabolismo
14.
Toxicol Lett ; 211(1): 54-61, 2012 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-22450445

RESUMO

Tri-ortho-cresyl phosphate (TOCP) has been widely used in industry and reported to induce delayed neurotoxicity in humans and animals. In addition, it is known to have a deleterious effect on the male reproductive system in animals, but the precise mechanism is yet to be elucidated. The present study shows that TOCP could disrupt the seminiferous epithelium in the mouse testis and decrease the sperm density in the epididymis in a dose-dependent manner. Neuropathy target esterase (NTE) was shown to exist in mouse spermatogenic cells, including spermatogonial stem cells and to be significantly inhibited by TOCP. Likewise, saligenin cyclic-o-tolyl phosphate (SCOTP), an activated metabolite of TOCP, markedly inhibited NTE activity in spermatogonial stem cells. Both inhibition of NTE activity by SCOTP and knockdown of NTE by shRNA remarkably inhibited cell proliferation. These results point to a role of NTE in regulating proliferation of mouse spermatogonial stem cells and provide a novel insight into the mechanism by which TOCP diminishes on the sperm number in the mouse testis.


Assuntos
Hidrolases de Éster Carboxílico/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Tritolil Fosfatos/farmacologia , Animais , Western Blotting , Hidrolases de Éster Carboxílico/fisiologia , Proliferação de Células/efeitos dos fármacos , Epididimo/efeitos dos fármacos , Epididimo/patologia , Masculino , Camundongos , Espermatogônias/crescimento & desenvolvimento , Células-Tronco/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia
15.
Toxicol Appl Pharmacol ; 256(3): 360-8, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21600909

RESUMO

Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and "ongoing inhibition") of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and the model applied and may be considered an external validation. The most sensitive component (Eα) for paraoxon (11-23% of activity, I(50) (30 min)=9-11 nM) is also the most sensitive for mipafox (I(50) (30 min)=4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (Eß, 71-84% of activity; I(50) (30 min)=1216 nM) is practically resistant to mipafox. The third component (Eγ, 5-8% of activity) is paraoxon resistant and has I(50) (30 min) of 3.4 µM with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies.


Assuntos
Encéfalo/efeitos dos fármacos , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Animais , Encéfalo/enzimologia , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/biossíntese , Hidrolases de Éster Carboxílico/metabolismo , Galinhas , Interações Medicamentosas , Indução Enzimática/efeitos dos fármacos , Isoflurofato/administração & dosagem , Isoflurofato/análogos & derivados , Isoflurofato/farmacologia , Cinética , Síndromes Neurotóxicas/metabolismo , Compostos Organofosforados/toxicidade , Paraoxon/administração & dosagem , Paraoxon/farmacologia
17.
J Plant Physiol ; 168(4): 337-43, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20727617

RESUMO

Degradation of chlorophylls during senescence is a highly regulated process which requires the concerted action of several enzymes. Traditionally, it has been stated that the dismantling process of the chlorophyll molecule begins with a dephytilation step, followed by Mg(2+) removal and other breakdown reactions. Recently, new evidence suggests the possibility of a rearrangement in the first two steps of this process, occurring Mg(2+) removal prior to the loss of the phytol side chain. With the purpose of approximating to the real sequential order of these reactions and to assess if dephytilation occurs on intact (catalyzed by chlorophyllase) or Mg-free (catalyzed by pheophytinase) chlorophyll, expression of both genes was analyzed in broccoli tissue during senescence. Samples of broccoli florets treated with plant hormones, such as cytokinin and ethylene were utilized, as to assess the effect of such compounds on the expression of these genes. Results showed that chlorophyllase expression did not correlate to typical expression patterns for genes related to senescence, since a decrease in expression during senescence was found for one of the two chlorophyllase genes analyzed, and the hormonal-treatment effects on gene expression did not match those observed on chlorophyll content for both chlorophyllase genes. Pheophytinase expression patterns, on the other hand, displayed an increase in the first 3 days of induced senescence, followed by lower expression values towards the end of the experiment. Samples subjected to postharvest treatments mostly showed an inhibition of pheophytinase expression, especially in samples in which degradation of chlorophylls had been delayed. These results suggest that pheophytinase expression correlates to the visual manifestation of postharvest treatments, supporting the possibility that this enzyme is responsible for the dephytilation step in chlorophyll breakdown.


Assuntos
Brassica/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Feofitinas/metabolismo , Envelhecimento , Sequência de Bases , Brassica/efeitos dos fármacos , Brassica/genética , Brassica/fisiologia , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/genética , Clorofila/metabolismo , Citocininas/farmacologia , Etilenos/farmacologia , Etiquetas de Sequências Expressas , Flores/efeitos dos fármacos , Flores/enzimologia , Flores/genética , Flores/fisiologia , Dados de Sequência Molecular , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
18.
Toxicol Sci ; 109(2): 276-85, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19349639

RESUMO

Neuropathy target esterase (NTE) is proven to act as a lysophospholipase (LysoPLA) in mice and phospholipase B (PLB) in cultured mammalian cells. In sensitive species, organophosphate (OP)-induced delayed neurotoxicity is initiated when NTE is inhibited by > 70% and then aged. It is hypothesized that homeostasis of phosphatidylcholine (PC) and/or lysophosphatidylcholine (LPC) in mice might be disrupted by the OPs since NTE and other phospholipases could be inhibited. To test this hypothesis, we treated mice using tri-o-cresyl phosphate (TOCP), which can inhibit and age NTE. Phenylmethylsulfonyl fluoride (PMSF), which inhibits NTE but cannot age, was used as a negative control. Effects on activity of NTE, LysoPLA, and PLB, the levels of PC, LPC, and glycerophosphocholine (GPC), and the aging of NTE in the brain, spinal cord, and sciatic nerve were examined. The results showed that the activities of NTE, NTE-LysoPLA, LysoPLA, NTE-PLB, and PLB were significantly inhibited in both TOCP- and PMSF-treated mice, and the inhibition of NTE and NTE-LysoPLA or NTE-PLB showed a high correlation coefficient. The NTE inhibited by TOCP was of the aged type, while nearly all NTE inhibited by PMSF was of the unaged type. Although the GPC level was remarkedly decreased, no significant change of PC and LPC levels was observed. However, the inhibition of these enzymes in mice by TOCP exhibited different characteristics from the TOCP-treated hens that we previously reported, which indicates that these enzymes were inhibited and then recovered more rapidly in mice than in hens. All results suggest that PC and LPC homeostasis was not disrupted in mice after exposure to TOCP. Differences in inhibition of NTE, LysoPLA, and PLB activities by TOCP between mice and hens may elucidate why these two species display different signs after exposure to the same neuropathic OPs.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Homeostase/efeitos dos fármacos , Lisofosfatidilcolinas/metabolismo , Fosfatidilcolinas/metabolismo , Tritolil Fosfatos/toxicidade , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Lisofosfolipase/metabolismo , Masculino , Camundongos , Síndromes Neurotóxicas/metabolismo , Fluoreto de Fenilmetilsulfonil/administração & dosagem , Fluoreto de Fenilmetilsulfonil/toxicidade , Fosforilação/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Tritolil Fosfatos/administração & dosagem
19.
Appl Biochem Biotechnol ; 151(2-3): 221-32, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18543118

RESUMO

New thermophilic and organic-solvent-tolerant Bacillus licheniformis S-86 strain is able to produce two active and solvent-stable esterases. Production of type I and II esterases was substantially enhanced when oils and surfactants were supplied as carbon sources. Grape oil (0.1% v/v) and Tween 20 to 60 (0.1% v/v) had enhanced enzyme production between 1.6- and 2.2-folds. Type II esterase was purified to homogeneity in a five-step procedure. This esterase was purified 76.7-fold with a specific activity of 135 U mg(-1). Molecular mass of the enzyme was estimated to be 38.4 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Type II esterase was active mostly on esters with short acyl chains, which allowed to classify the enzyme as a carboxylesterase with a K (m) of 80.2 mmol l(-1) and a V (max) of 256.4 micromol min(-1) mg(-1) for p-nitrophenyl acetate. Also, B. licheniformis S-86 type II esterase displayed activity in presence of water-miscible organic solvents at 50% concentration and stability after 1-h incubation.


Assuntos
Bacillus/enzimologia , Hidrolases de Éster Carboxílico/biossíntese , Bacillus/efeitos dos fármacos , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Cinética , Óleos de Plantas/farmacologia , Polissorbatos/farmacologia , Solventes/farmacologia , Especificidade por Substrato , Tensoativos/farmacologia , Vitis
20.
J Food Sci ; 73(5): C432-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18576990

RESUMO

Utilization of phenolic acids, including gallic acid, coumaric acid, caffic acid, cinnamic acid, and ferulic acid, for methanol reduction in wine was investigated. Enzyme activities of pectinesterase and pectin lyase decreased significantly when 0.1 mg/L of gallic acid, coumaric acid, caffic acid, cinnamic acid, or ferulic acid was added. However, no inhibition on polygalacturonase activity was observed when 0.5 mg/L of phenolic acid was added. Methanol content in commercial pectic enzyme (CPE) group increased from 11.53 +/- 1.34 to 56.67 +/- 3.75 ppm in the final products. Adding gallic acid or coumaric acid with CPE inhibited the increase of methanol production. In addition, when 0.2 mg/L of phenolic acid (gallic acid or coumaric acid) was added, the amount of total phenolic acid released from CPE + gallic acid or CPE + coumaric acid groups became higher than CPE group by approximately 466 and 539 mg/L, respectively. In conclusion, the values of lightness, red content, yellow content, total pigment, and total phenolic acid increased in the presence of gallic acid or coumaric acid with CPE, suggesting that adding gallic acid or coumaric acid into winemaking process is a potential method for reducing methanol content, improving wine quality, as well as increasing healthy compounds in wine production.


Assuntos
Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidroxibenzoatos/metabolismo , Metanol/metabolismo , Poligalacturonase/efeitos dos fármacos , Polissacarídeo-Liases/efeitos dos fármacos , Vinho/análise , Ácidos Cafeicos , Hidrolases de Éster Carboxílico/metabolismo , Cinamatos , Ácidos Cumáricos , Ácido Gálico , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Metanol/análise , Metanol/química , Poligalacturonase/metabolismo , Polissacarídeo-Liases/metabolismo , Vinho/normas
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