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1.
Adv Ther ; 37(8): 3537-3550, 2020 08.
Article in English | MEDLINE | ID: mdl-32564268

ABSTRACT

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.


Subject(s)
Antithrombins/therapeutic use , Dabigatran/pharmacokinetics , Genotype , Pantoprazole/pharmacokinetics , Pharmacogenetics , Polymorphism, Genetic , Thrombosis/drug therapy , ATP Binding Cassette Transporter, Subfamily B/drug effects , Adolescent , Adult , Anticoagulants/pharmacology , Anticoagulants/therapeutic use , Antithrombins/pharmacokinetics , Area Under Curve , Carboxylic Ester Hydrolases/drug effects , Cytochrome P-450 CYP2D6/drug effects , Cytochrome P-450 CYP3A/drug effects , Dabigatran/therapeutic use , Female , Humans , Male , Middle Aged , Organic Cation Transporter 1/drug effects , Pantoprazole/therapeutic use , Proton Pump Inhibitors/pharmacokinetics , Proton Pump Inhibitors/therapeutic use , Sex Factors , Spain , Young Adult
2.
Exp Neurol ; 324: 113128, 2020 02.
Article in English | MEDLINE | ID: mdl-31759899

ABSTRACT

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.


Subject(s)
Alzheimer Disease/drug therapy , Astrocytes/drug effects , Astrocytes/metabolism , Carboxylic Ester Hydrolases/drug effects , Cell Adhesion Molecules/drug effects , Kelch-Like ECH-Associated Protein 1/drug effects , MicroRNAs/metabolism , NF-E2-Related Factor 2/drug effects , Oxidative Stress/drug effects , Signal Transduction/drug effects , Alzheimer Disease/metabolism , Alzheimer Disease/psychology , Amyloid beta-Peptides , Animals , Computational Biology , Galactose , Male , Maze Learning , Peptide Fragments , Rats , Rats, Sprague-Dawley
3.
Eur J Med Chem ; 175: 2-19, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31055149

ABSTRACT

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.


Subject(s)
Alzheimer Disease/drug therapy , Pyrazoles/chemistry , Pyrazoles/therapeutic use , Pyridines/chemistry , Pyridines/therapeutic use , Acetylcholinesterase/drug effects , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/ultrastructure , Antioxidants/pharmacology , Carboxylic Ester Hydrolases/drug effects , Chelating Agents/therapeutic use , Cholinesterase Inhibitors/therapeutic use , Copper/chemistry , Crystallography, X-Ray , Drug Evaluation, Preclinical , Humans , Inhibitory Concentration 50 , Microscopy, Electron, Transmission , Molecular Docking Simulation , Pyrazoles/chemical synthesis , Pyridines/chemical synthesis , Spectrometry, Fluorescence
4.
Folia Neuropathol ; 56(3): 179-186, 2018.
Article in English | MEDLINE | ID: mdl-30509039

ABSTRACT

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.


Subject(s)
Brain Injuries, Traumatic/pathology , Brain/drug effects , Histone Deacetylase Inhibitors/pharmacology , Signal Transduction/drug effects , Vorinostat/pharmacology , Animals , Brain/metabolism , Brain/pathology , Brain Injuries, Traumatic/metabolism , Carboxylic Ester Hydrolases/biosynthesis , Carboxylic Ester Hydrolases/drug effects , Male , Mice , Mice, Inbred ICR , NF-E2-Related Factor 2/biosynthesis , NF-E2-Related Factor 2/drug effects , Neuroprotective Agents/pharmacology , Nitric Oxide Synthase Type II/biosynthesis , Nitric Oxide Synthase Type II/drug effects
5.
Toxicology ; 410: 73-82, 2018 12 01.
Article in English | MEDLINE | ID: mdl-30176330

ABSTRACT

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.


Subject(s)
Brain/enzymology , Carboxylic Ester Hydrolases/drug effects , Chickens/metabolism , Cholinesterase Inhibitors/pharmacology , Cholinesterases/drug effects , Organophosphorus Compounds/pharmacology , Animals , Binding, Competitive/drug effects , Brain/drug effects , Kinetics , Membranes/drug effects , Membranes/enzymology
6.
Toxicology ; 410: 10-15, 2018 12 01.
Article in English | MEDLINE | ID: mdl-30172647

ABSTRACT

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.


Subject(s)
Chemical Warfare Agents/toxicity , Esterases/drug effects , Esterases/metabolism , Mice, Inbred Strains , Nerve Agents/toxicity , Sarin/toxicity , Acetylcholinesterase/drug effects , Acetylcholinesterase/metabolism , Animals , Butyrylcholinesterase/drug effects , Butyrylcholinesterase/metabolism , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/metabolism , Cholinesterase Inhibitors/toxicity , Erythrocytes/drug effects , Erythrocytes/enzymology , Female , Injections, Subcutaneous , Lethal Dose 50 , Male , Mice , Species Specificity
7.
Appl Microbiol Biotechnol ; 101(10): 4201-4213, 2017 May.
Article in English | MEDLINE | ID: mdl-28224194

ABSTRACT

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.


Subject(s)
Bridged-Ring Compounds/pharmacology , Cell Proliferation/drug effects , Glycolysis/drug effects , Pentose Phosphate Pathway/drug effects , Pyrones/pharmacology , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/genetics , Cell Cycle/drug effects , Electrophoresis, Gel, Two-Dimensional , Glucose/metabolism , Glycolysis/genetics , HeLa Cells , Hexokinase/drug effects , Hexokinase/genetics , Humans , Oxidation-Reduction , Pentose Phosphate Pathway/genetics , Proteomics , Triose-Phosphate Isomerase/drug effects , Triose-Phosphate Isomerase/genetics
8.
Acta Trop ; 163: 167-78, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27443607

ABSTRACT

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.


Subject(s)
Aedes/drug effects , Andrographis , Dengue/prevention & control , Diterpenes/pharmacology , Insecticides/pharmacology , Larva/drug effects , Mosquito Vectors/drug effects , Plant Extracts/pharmacology , Animals , Carboxylic Ester Hydrolases/drug effects , Chromatography, Gas , Chromatography, High Pressure Liquid , Cytochrome P-450 Enzyme System/drug effects , Female , Glutathione Transferase/drug effects , Mass Spectrometry , Mosquito Control , Oviposition/drug effects , Plant Leaves
9.
Article in English | MEDLINE | ID: mdl-25151331

ABSTRACT

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.


Subject(s)
Chromatography, High Pressure Liquid/methods , Epothilones/blood , Epothilones/chemistry , Phenylmethylsulfonyl Fluoride/chemistry , Tandem Mass Spectrometry/methods , Animals , Carboxylic Ester Hydrolases/antagonists & inhibitors , Carboxylic Ester Hydrolases/drug effects , Drug Stability , Epothilones/pharmacokinetics , Female , Linear Models , Phenylmethylsulfonyl Fluoride/pharmacology , Rats , Reproducibility of Results , Sensitivity and Specificity
10.
Food Sci Technol Int ; 20(4): 287-98, 2014 Jun.
Article in English | MEDLINE | ID: mdl-23751545

ABSTRACT

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.


Subject(s)
Blueberry Plants/chemistry , Cell Wall/chemistry , Cold Temperature , Cyclopropanes/pharmacology , Food Quality , Food Storage/methods , Analysis of Variance , Blueberry Plants/drug effects , Carboxylic Ester Hydrolases/analysis , Carboxylic Ester Hydrolases/drug effects , Cell Wall/drug effects , Ethylenes/analysis , Hydrolases/analysis , Hydrolases/drug effects , Pectins/analysis , Polygalacturonase/analysis , Polygalacturonase/drug effects , Polysaccharides/analysis , Time Factors
11.
Food Sci Technol Int ; 20(4): 309-17, 2014 Jun.
Article in English | MEDLINE | ID: mdl-23744122

ABSTRACT

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.


Subject(s)
Carica/drug effects , Carica/enzymology , Cell Wall/drug effects , Food Storage/methods , Nitric Oxide/pharmacology , Plant Growth Regulators/metabolism , Abscisic Acid/analysis , Abscisic Acid/metabolism , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/metabolism , Cellulase/drug effects , Cellulase/metabolism , Ethylenes/metabolism , Free Radical Scavengers/pharmacology , Gibberellins/analysis , Gibberellins/metabolism , Indoleacetic Acids/analysis , Indoleacetic Acids/metabolism , Isopentenyladenosine/analogs & derivatives , Isopentenyladenosine/analysis , Isopentenyladenosine/metabolism , Plant Growth Regulators/analysis , Polygalacturonase/drug effects , Polygalacturonase/metabolism , Polysaccharide-Lyases/drug effects , Polysaccharide-Lyases/metabolism
12.
Appl Biochem Biotechnol ; 170(3): 654-75, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23604968

ABSTRACT

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.


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Actinomycetales/enzymology , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/isolation & purification , Cloning, Molecular , Culture Media , Enzyme Stability , Escherichia coli/genetics , Hydrogen-Ion Concentration , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Solvents/pharmacology , Temperature
13.
Planta ; 236(4): 989-97, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22526505

ABSTRACT

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.


Subject(s)
Arabidopsis/metabolism , Cadmium/toxicity , Cell Wall/metabolism , Phosphorus/deficiency , Polysaccharides/metabolism , Arabidopsis/chemistry , Arabidopsis/drug effects , Cadmium/analysis , Cadmium/metabolism , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/metabolism , Cell Wall/chemistry , Cell Wall/drug effects , Chlorophyll/metabolism , Citric Acid/analysis , Citric Acid/metabolism , Lipid Peroxidation/drug effects , Pectins/analysis , Pectins/metabolism , Plant Exudates/chemistry , Plant Roots/chemistry , Plant Roots/drug effects , Plant Roots/metabolism , Plant Shoots/chemistry , Plant Shoots/drug effects , Plant Shoots/metabolism , Polysaccharides/analysis , Seedlings/chemistry , Seedlings/drug effects , Seedlings/metabolism , Uronic Acids/analysis , Uronic Acids/metabolism
14.
Toxicol Lett ; 211(1): 54-61, 2012 May 20.
Article in English | MEDLINE | ID: mdl-22450445

ABSTRACT

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.


Subject(s)
Carboxylic Ester Hydrolases/drug effects , Spermatogenesis/drug effects , Spermatogonia/drug effects , Tritolyl Phosphates/pharmacology , Animals , Blotting, Western , Carboxylic Ester Hydrolases/physiology , Cell Proliferation/drug effects , Epididymis/drug effects , Epididymis/pathology , Male , Mice , Spermatogonia/growth & development , Stem Cells/drug effects , Testis/drug effects , Testis/pathology
15.
Toxicol Appl Pharmacol ; 256(3): 360-8, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21600909

ABSTRACT

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.


Subject(s)
Brain/drug effects , Carboxylic Ester Hydrolases/drug effects , Neurotoxicity Syndromes/etiology , Animals , Brain/enzymology , Carboxylic Ester Hydrolases/antagonists & inhibitors , Carboxylic Ester Hydrolases/biosynthesis , Carboxylic Ester Hydrolases/metabolism , Chickens , Drug Interactions , Enzyme Induction/drug effects , Isoflurophate/administration & dosage , Isoflurophate/analogs & derivatives , Isoflurophate/pharmacology , Kinetics , Neurotoxicity Syndromes/metabolism , Organophosphorus Compounds/toxicity , Paraoxon/administration & dosage , Paraoxon/pharmacology
17.
J Plant Physiol ; 168(4): 337-43, 2011 Mar 01.
Article in English | MEDLINE | ID: mdl-20727617

ABSTRACT

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.


Subject(s)
Brassica/enzymology , Carboxylic Ester Hydrolases/metabolism , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Plant , Pheophytins/metabolism , Aging , Base Sequence , Brassica/drug effects , Brassica/genetics , Brassica/physiology , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/genetics , Chlorophyll/metabolism , Cytokinins/pharmacology , Ethylenes/pharmacology , Expressed Sequence Tags , Flowers/drug effects , Flowers/enzymology , Flowers/genetics , Flowers/physiology , Molecular Sequence Data , Plant Growth Regulators/pharmacology , Plant Proteins/drug effects , Plant Proteins/genetics , Plant Proteins/metabolism , Sequence Alignment
18.
Toxicol Sci ; 109(2): 276-85, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19349639

ABSTRACT

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.


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Homeostasis/drug effects , Lysophosphatidylcholines/metabolism , Phosphatidylcholines/metabolism , Tritolyl Phosphates/toxicity , Analysis of Variance , Animals , Brain/drug effects , Brain/metabolism , Carboxylic Ester Hydrolases/drug effects , Lysophospholipase/metabolism , Male , Mice , Neurotoxicity Syndromes/metabolism , Phenylmethylsulfonyl Fluoride/administration & dosage , Phenylmethylsulfonyl Fluoride/toxicity , Phosphorylation/drug effects , Sciatic Nerve/drug effects , Sciatic Nerve/metabolism , Spinal Cord/drug effects , Spinal Cord/metabolism , Tritolyl Phosphates/administration & dosage
19.
Appl Biochem Biotechnol ; 151(2-3): 221-32, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18543118

ABSTRACT

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.


Subject(s)
Bacillus/enzymology , Carboxylic Ester Hydrolases/biosynthesis , Bacillus/drug effects , Carboxylic Ester Hydrolases/drug effects , Carboxylic Ester Hydrolases/isolation & purification , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Kinetics , Plant Oils/pharmacology , Polysorbates/pharmacology , Solvents/pharmacology , Substrate Specificity , Surface-Active Agents/pharmacology , Vitis
20.
J Food Sci ; 73(5): C432-7, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18576990

ABSTRACT

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.


Subject(s)
Carboxylic Ester Hydrolases/drug effects , Hydroxybenzoates/metabolism , Methanol/metabolism , Polygalacturonase/drug effects , Polysaccharide-Lyases/drug effects , Wine/analysis , Caffeic Acids , Carboxylic Ester Hydrolases/metabolism , Cinnamates , Coumaric Acids , Gallic Acid , Hydroxybenzoates/analysis , Hydroxybenzoates/chemistry , Methanol/analysis , Methanol/chemistry , Polygalacturonase/metabolism , Polysaccharide-Lyases/metabolism , Wine/standards
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