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1.
Front Chem ; 8: 826, 2020.
Article in English | MEDLINE | ID: mdl-33195036

ABSTRACT

In this study, pretilachlor was encapsulated into polyurea microcapsules prepared by water-initiated polymerization of polyaryl polymethylene isocyanate and eventually made into pretilachlor microcapsules suspension (PMS). We used response surface methodology (RSM) combined with the Box-Behnken design (BBD) model to optimize the formulation of PMS. The encapsulation efficiency (EE) of PMS was investigated with respect to three independent variables including wall material dosage (X1), emulsifier dosage (X2), and polymerization stirring speed (X3). The results showed that the regression equation model had a satisfactory accuracy in predicting the EE of PMS. To achieve an optimal condition for PMS preparation, the dose of wall material was set to 5%, the dose of emulsifier was set to 3.5% and the polymerization stirring speed was set to 200 rpm. The EE of PMS was up to 95.68% under the optimized condition, and the spherical shape with smooth surface morphology was observed. PMS was also proven to have delayed release capability and in vivo herbicidal activity against barnyard grass [Echinochloa crusgalli (L.) Beauv.] with an LC50 value of 274 mg/L. Furthermore, PMS had efficient weed management compared to commercially available 30% pretilachlor emulsifier (PE), showing a promising potential application for weeding paddy fields.

2.
Ecotoxicol Environ Saf ; 205: 111374, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32977284

ABSTRACT

Phenazines, a large group of nitrogen-containing heterocycles with promising bioactivities, can be widely used as medicines and pesticides. But phenazines also generate toxicity risks due to their non-selective DNA binding. The environmental fate of phenazines in soils is the key to assess their risks; however, hitherto, there have been very few related studies. Therefore in the present study, the degradation, adsorption and leaching behaviors of a typical natural phenazine-phenazine-1-carboxamide (PCN) in agricultural soils from three representative places in China with different physicochemical properties were, for the first time, systematically studied in laboratory simulation experiments. Our results indicated that the degradation of PCN in all the tested soils followed the first order kinetics, with half-lives ranging from 14.4 to 57.8 d under different conditions. Soil anaerobic microorganisms, organic matter content and pH conditions are important factors that regulating PCN degradation. The adsorption data of PCN were found to be well fitted using the Freundlich model, with the r2 values above 0.978. Freundlich adsorption coefficient Kf of PCN ranged from 5.75 to 12.8 [(mg/kg)/(mg/L)1/n] in soils. The retention factor Rf values ranged from 0.0833 to 0.354, which means that the mobility of PCN in the three types of soil is between immobile to moderately mobile. Our results demonstrate that PCN is easily degraded, has high adsorption affinity and low mobility in high organic matter content and clay soils, thus resulting in lower risks of contamination to groundwater systems. In contrast, it degraded slowly, has low adsorption affinity and moderately mobile in soils with low organic matter and clay content, therefore it has higher polluting potential to groundwater systems. Overall, these findings provide useful insights into the future evaluation of environmental as well as health risks of PCN.


Subject(s)
Phenazines/analysis , Soil Pollutants/analysis , Adsorption , Agriculture , China , Clay , Groundwater , Kinetics , Pesticides , Soil/chemistry
3.
Bioorg Med Chem Lett ; 29(11): 1430-1433, 2019 06 01.
Article in English | MEDLINE | ID: mdl-30975625

ABSTRACT

A series of nitropyridyl-based dichloropropene ethers were prepared and evaluated for their insecticidal activities against main lepidopteran pests such as M. separate, P. xylostella and P. litura. The compounds showed a broad-spectrum of remarkable insecticidal activities. Especially 4a (2,6-dichloro-4-(3,3-dichloroallyloxy)phenyl 3-[5-nitro-2-pyridyloxy]propyl ether) and 11a (2-(4-(3-(2,6-dichloro-4-((3,3-dichloroallyl)oxy)phenoxy)propoxy)phenoxy)-5-nitropyridine) displayed potent activities comparable to that of Pyridalyl, the only commercialized dichloropropene ether insecticide thus far. The structure-activity relationship was also discussed.


Subject(s)
Ethers/pharmacology , Insecticides/pharmacology , Pyridines/pharmacology , Animals , Ethers/chemical synthesis , Insecticides/chemical synthesis , Molecular Structure , Moths/drug effects , Pyridines/chemical synthesis , Structure-Activity Relationship
4.
Chemosphere ; 177: 65-76, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28284117

ABSTRACT

Organochlorine pesticides (OCPs) in sediment were a potential damage for humans and ecosystems. The aim of this work was to determine the effectiveness of carbon materials remedy hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethanes (DDTs) in sediment. Two different carbon materials including activated carbon (AC) and multi-walled carbon nanotubes (MWCNTs) were used in the present research. Sediment treated with 2 wt% AC and MWCNTs after 150 d contact showed 97%, and 75% reduction for HCH, and 93% and 59% decrease for DDTs in aqueous equilibrium concentration, respectively. Similarly, the reduction efficiencies of DDT and HCH uptake by semipermeable membrane devices (SPMDs) treated with AC (MWCNTs) were 97% (75%) and 92% (63%), respectively under the identical conditions. Furthermore, for 2 wt% AC (MWCNTs) system, a reduction of XAD beads uptake up to 87% (52%) and 73% (67%) was obtained in HCH and DDT flux to overlying water in quiescent system. Adding MWCNTs to contaminated sediment did not significantly decrease aqueous equilibrium concentration and DDTs and HCH availability in SPMDs compared to AC treatment. A series of results indicated that AC had significantly higher remediation efficiency towards HCH and DDTs in sediment than MWCNTs. Additionally, the removal efficiencies of two organic pollutants improved with increasing material doses and contact times. The greater effectiveness of AC was attributed to its greater specific surface area, which was favorable for binding contaminants. These results highlighted the potential for using AC as in-situ sorbent amendments for sediment remediation.


Subject(s)
Charcoal/chemistry , Environmental Restoration and Remediation/methods , Hydrocarbons, Chlorinated/analysis , Nanotubes, Carbon/chemistry , Water Pollutants, Chemical/analysis , Adsorption , China , DDT/analysis , Geography , Geologic Sediments/chemistry , Hexachlorocyclohexane/analysis , Lakes/chemistry , Pesticides/analysis , Solubility , Water/chemistry
5.
Alcohol Clin Exp Res ; 40(11): 2320-2328, 2016 11.
Article in English | MEDLINE | ID: mdl-27647657

ABSTRACT

BACKGROUND: Ethanol (EtOH) neurotoxicity can result in devastating effects on brain and behavior by disrupting homeostatic signaling cascades and inducing cell death. One such mechanism involves double-stranded RNA activated protein kinase (PKR), a primary regulator of protein translation and cell viability in the presence of a virus or other external stimuli. EtOH-mediated up-regulation of interferon-gamma (IFN-γ; the oxidative stress-inducible regulator of PKR), PKR, and its target, p53, are still being fully elucidated. METHODS: Using Western blot analysis, immunofluorescence, and linear regression analyses, changes in the IFN-γ-PKR-p53 pathway following chronic EtOH treatment in the frontal cortex of rodents were examined. The role of PKR on cell viability was also assessed in EtOH-treated cells using PKR overexpression vector and PKR inhibitor (PKRI). RESULTS: In rats chronically fed EtOH, PKR, phosphorylated PKR (p-PKR), IFN-γ, and p53 were significantly increased following chronic EtOH exposure. Linear regression revealed a significant correlation between IFN-γ and p-PKR protein levels, as well as p-PKR expression and age of EtOH exposure. Overexpression of PKR resulted in greater cell death, while use of PKRI enhanced cell viability in EtOH-treated cells. CONCLUSIONS: Chronic EtOH exposure activates the IFN-γ-PKR-p53 pathway in the frontal cortex of rodents. p-PKR expression is greater in brains of rodents exposed to EtOH at earlier ages compared to later life, suggesting a mechanism by which young brains could be more susceptible to EtOH-related brain injury. PKR and p-PKR were also colocalized in neurons and astrocytes of rats. This study provides additional insight into biochemical mechanisms underlying alcohol use disorder related neuropathology and warrants further investigation of PKR as a potential pharmacotherapeutic target to combat EtOH-related neurotoxicity, loss of protein translation and brain injury.


Subject(s)
Central Nervous System Depressants/pharmacology , Ethanol/pharmacology , Interferon-gamma/metabolism , Prefrontal Cortex/drug effects , Tumor Suppressor Protein p53/metabolism , eIF-2 Kinase/metabolism , Age of Onset , Animals , Cell Death/drug effects , Cell Line, Tumor , Humans , Male , Prefrontal Cortex/metabolism , Random Allocation , Rats, Wistar , Signal Transduction/drug effects , Up-Regulation/drug effects
6.
J Colloid Interface Sci ; 471: 94-102, 2016 Jun 01.
Article in English | MEDLINE | ID: mdl-26994349

ABSTRACT

Silver nanoparticle-decorated magnetic graphene oxide (MGO-Ag) was synthesized by doping silver and Fe3O4 nanoparticles on the surface of GO, which was used as an antibacterial agent. MGO-Ag was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray (EDS), X-ray diffraction (XRD), Raman spectroscopy and magnetic property tests. It can be found that magnetic iron oxide nanoparticles and nano-Ag was well dispersed on graphene oxide; and MGO-Ag exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus. Several factors were investigated to study the antibacterial effect of MGO-Ag, such as temperature, time, pH and bacterial concentration. We also found that MGO-Ag maintained high inactivation rates after use six times and can be separated easily after antibacterial process. Moreover, the antibacterial mechanism is discussed and the synergistic effect of GO, Fe3O4 nanoparticles and nano-Ag accounted for high inactivation of MGO-Ag.


Subject(s)
Anti-Bacterial Agents , Escherichia coli/growth & development , Graphite/chemistry , Metal Nanoparticles/chemistry , Silver/chemistry , Staphylococcus aureus/growth & development , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Metal Nanoparticles/ultrastructure
7.
Neuropharmacology ; 105: 329-340, 2016 06.
Article in English | MEDLINE | ID: mdl-26805422

ABSTRACT

Binge drinking induces several neurotoxic consequences including oxidative stress and neurodegeneration. Because of these effects, drugs which prevent ethanol-induced damage to the brain may be clinically beneficial. In this study, we investigated the ethanol-mediated KLF11-MAO cell death cascade in the frontal cortex of Sprague-Dawley rats exposed to a modified Majchowicz 4-day binge ethanol model and control rats. Moreover, MAO inhibitors (MAOIs) were investigated for neuroprotective activity against binge ethanol. Binge ethanol-treated rats demonstrated a significant increase in KLF11, both MAO isoforms, protein oxidation and caspase-3, as well as a reduction in BDNF expression in the frontal cortex compared to control rats. MAOIs prevented these binge ethanol-induced changes, suggesting a neuroprotective benefit. Neither binge ethanol nor MAOI treatment significantly affected protein expression levels of the oxidative stress enzymes, SOD2 or catalase. Furthermore, ethanol-induced antinociception was enhanced following exposure to the 4-day ethanol binge. These results demonstrate that the KLF11-MAO pathway is activated by binge ethanol exposure and MAOIs are neuroprotective by preventing the binge ethanol-induced changes associated with this cell death cascade. This study supports KLF11-MAO as a mechanism of ethanol-induced neurotoxicity and cell death that could be targeted with MAOI drug therapy to alleviate alcohol-related brain injury. Further examination of MAOIs to reduce alcohol use disorder-related brain injury could provide pivotal insight to future pharmacotherapeutic opportunities.


Subject(s)
Binge Drinking/enzymology , Brain Diseases/prevention & control , Central Nervous System Depressants/toxicity , Ethanol/toxicity , Monoamine Oxidase Inhibitors/therapeutic use , Monoamine Oxidase/genetics , Signal Transduction/drug effects , Trans-Activators/drug effects , Trans-Activators/genetics , Animals , Brain Diseases/chemically induced , Brain-Derived Neurotrophic Factor/metabolism , Caspase 3/metabolism , Cell Death , Central Nervous System Depressants/administration & dosage , Central Nervous System Depressants/antagonists & inhibitors , Ethanol/administration & dosage , Ethanol/antagonists & inhibitors , Male , Neuroprotective Agents/pharmacology , Neurotoxicity Syndromes/prevention & control , Oxidative Stress/drug effects , Pain Measurement/drug effects , Rats , Rats, Sprague-Dawley
8.
Int J Biol Macromol ; 82: 702-10, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26582339

ABSTRACT

Magnetic chitosan-graphene oxide (MCGO) nanocomposite was prepared as a multi-functional nanomaterial for the applications of antibacterial and dye removal. The nanocomposite was characterized by scanning electronic microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectrometer (FTIR). The antibacterial performance for MCGO against Escherichia coli was varied depending on the concentration of MCGO. SEM images of E. coli cells demonstrated that the antimicrobial performance of MCGO nanocomposite was possibly due to the damage of cell membrane. This work also explored MCGO's adsorption performance for methyl orange (MO). The experimental parameters including adsorbent mass, pH value, contact time and concentration of MO on the adsorption capacity were investigated. The maximum adsorption capacity of MCGO for MO was 398.08 mg/g. This study showed that the MCGO offered enormous potential applications for water treatment.


Subject(s)
Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Chitosan/chemistry , Coloring Agents/chemistry , Graphite/chemistry , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Oxides/chemistry , Adsorption , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cell Membrane/drug effects , Escherichia coli/drug effects , Escherichia coli/ultrastructure , Hydrogen-Ion Concentration , Magnetite Nanoparticles/ultrastructure , Microbial Sensitivity Tests , Nanocomposites/ultrastructure , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
9.
Neurotox Res ; 28(1): 18-31, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25739536

ABSTRACT

Major depressive disorder and alcoholism are significant health burdens that can affect executive functioning, cognitive ability, job responsibilities, and personal relationships. Studies in animal models related to depression or alcoholism reveal that the expression of Krüppel-like factor 11 (KLF11, also called TIEG2) is elevated in frontal cortex, which suggests that KLF11 may play a role in stress- or ethanol-induced psychiatric conditions. KLF11 is a transcriptional activator of monoamine oxidase A and B, but also serves other functions in cell cycle regulation and apoptotic cell death. In the present study, immunohistochemistry was used to quantify intensity of nuclear KLF11, combined with an unbiased stereological approach to assess nuclei in fronto-limbic, limbic, and other brain regions of rats exposed chronically to social defeat or ethanol. KLF11 immunoreactivity was increased significantly in the medial prefrontal cortex, frontal cortex, and hippocampus of both stressed rats and rats fed ethanol. However, expression of KLF11 protein was not significantly affected in the thalamus, hypothalamus, or amygdala in either treatment group compared to respective control rats. Triple-label immunofluorescence revealed that KLF11 protein was localized in nuclei of neurons and astrocytes. KLF11 was also co-localized with the immunoreactivity of cleaved caspase-3. In addition, Western blot analysis revealed a significant reduction in anti-apoptotic protein, Bcl-xL, but an increase of caspase-3 expression in the frontal cortex of ethanol-treated rats compared to ethanol-preferring controls. Thus, KLF11 protein is up-regulated following chronic exposure to stress or ethanol in a region-specific manner and may contribute to pro-apoptotic signaling in ethanol-treated rats. Further investigation into the KLF11 signaling cascade as a mechanism for neurotoxicity and cell death in depression and alcoholism may provide novel pharmacological targets to lessen brain damage and maximize neuroprotection in these disorders.


Subject(s)
Apoptosis , Brain/metabolism , Ethanol/administration & dosage , Stress, Psychological/metabolism , Trans-Activators/metabolism , Animals , Apoptosis/drug effects , Astrocytes/drug effects , Astrocytes/metabolism , Brain/drug effects , Caspase 3/metabolism , Dominance-Subordination , Ethanol/pharmacology , Hippocampus/drug effects , Hippocampus/metabolism , Male , Neurons/drug effects , Neurons/metabolism , Prefrontal Cortex/drug effects , Prefrontal Cortex/metabolism , Rats , Rats, Wistar , bcl-X Protein/metabolism
10.
Alcohol Clin Exp Res ; 39(3): 476-84, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25704249

ABSTRACT

BACKGROUND: Brain cell death is a major pathological consequence of alcohol neurotoxicity. However, the molecular cascades in alcohol-induced brain tissue injury are unclear. METHODS: Using Western blot and double immunofluorescence, we examined the expression of interferon (IFN)-induced protein kinase R (PKR), phosphorylated-PKR (p-PKR), and IFN gamma (IFNγ) in the prefrontal cortex (PFC) of postmortem brains from subjects with alcohol use disorders (AUD). RESULTS: The protein levels of PKR, p-PKR, and IFNγ were significantly increased in subjects with AUD compared with control subjects without AUD, and a younger age of onset of AUD was significantly correlated with higher protein levels of p-PKR. In addition, elevated PKR- and p-PKR-IR were observed in both neurons and astrocytes in the PFC of subjects with AUD compared to subjects without AUD. CONCLUSIONS: The activation of the IFNγ-PKR pathway in PFC of humans is associated with chronic excessive ethanol use with an age of onset dependent manner, and activation of this pathway may play a pivotal role in AUD-related brain tissue injury. This study provides insight into neurodegenerative key factors related to AUD and identifies potential targets for the treatment of alcohol-induced neurotoxicity.


Subject(s)
Alcohol-Related Disorders/metabolism , Interferon-gamma/biosynthesis , Prefrontal Cortex/metabolism , Signal Transduction , eIF-2 Kinase/biosynthesis , Adult , Alcohol-Related Disorders/pathology , Female , Humans , Male , Middle Aged , Prefrontal Cortex/pathology , Signal Transduction/physiology
11.
Neuropsychopharmacology ; 40(6): 1373-82, 2015 May.
Article in English | MEDLINE | ID: mdl-25502632

ABSTRACT

The biochemical pathways underlying major depressive disorder (MDD) and chronic stress are not well understood. However, it has been reported that monoamine oxidase A (MAO A, a major neurotransmitter-degrading enzyme) is significantly increased in the brains of human subjects affected with MDD and rats exposed to chronic social defeat (CSD) stress, which is used to model depression. In the current study, we compared the protein levels of a MAO A-transcriptional activator, Kruppel-like factor 11 (KLF11 , also recognized as transforming growth factor-beta-inducible early gene 2) between the brains of 18 human subjects with MDD and 18 control subjects. We found that, indeed, the expression of KLF11 is increased by 36% (p<0.02) in the postmortem prefrontal cortex of human subjects with MDD compared with controls. We also observed a positive correlation between KLF11 levels and those of its target gene, MAO A, both in association with MDD. KLF11 protein expression was also increased by 44% (p<0.02) in the frontal cortex of KLF11 wild-type mice (Klf11(+/+)) vs Klf11(-/-) when both exposed to CSD stress. In contrast, locomotor activities, central box duration and sucrose preference were significantly reduced in the stressed Klf11(+/+) mice, suggesting that Klf11(+/+) mice are more severely affected by the stress model compared with Klf11(-/-) mice. These results serve to assign an important role of KLF11 in upregulating MAO A in MDD and chronic social stress, suggesting that inhibition of the pathways regulated by this transcription factor may aid in the therapeutics of neuropsychiatric illnesses. Thus, the new knowledge derived from the current study extends our understanding of transcriptional mechanisms that are operational in the pathophysiology of common human diseases and thus bears significant biomedical relevance.


Subject(s)
Cell Cycle Proteins/metabolism , DNA-Binding Proteins/metabolism , Depressive Disorder, Major/metabolism , Frontal Lobe/metabolism , Monoamine Oxidase/metabolism , Repressor Proteins/metabolism , Stress, Psychological/metabolism , Transcription Factors/metabolism , Animals , Apoptosis Regulatory Proteins , Chronic Disease , DNA-Binding Proteins/genetics , Disease Models, Animal , Dominance-Subordination , Female , Humans , Male , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Motor Activity/physiology , Severity of Illness Index , Transcription Factors/genetics , Up-Regulation
12.
Alcohol Clin Exp Res ; 38(2): 401-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24428663

ABSTRACT

BACKGROUND: Alcohol (EtOH [ethanol]) is an antinociceptive agent, working in part, by reducing sensitivity to painful stimuli. The transcription factor Kruppel-like factor 11 (KLF11), a human diabetes-causing gene that also regulates the neurotransmitter metabolic enzymes monoamine oxidase (MAO), has recently been identified as an EtOH-inducible gene. However, its role in antinociception remains unknown. Consequently, we investigated the function of KLF11 in chronic EtOH-induced antinociception using a genetically engineered knockout mouse model. METHODS: Wild-type (Klf11(+/+) ) and KLF11 knockout (Klf11(-/-) ) mice were fed a liquid diet containing EtOH for 28 days with increasing amounts of EtOH from 0% up to a final concentration of 6.4%, representing a final diet containing 36% of calories primarily from EtOH. Control mice from both genotypes were fed liquid diet without EtOH for 28 days. The EtOH-induced antinociceptive effect was determined using the tail-flick test before and after EtOH exposure (on day 29). In addition, the enzyme activity and mRNA levels of MAO A and MAO B were measured by real-time RT-PCR and enzyme assays, respectively. RESULTS: EtOH produced an antinociceptive response to thermal pain in Klf11(+/+) mice, as expected. In contrast, deletion of KLF11 in the Klf11(-/-) mice abolished the EtOH-induced antinociceptive effect. The mRNA and protein levels of KLF11 were significantly increased in the brain prefrontal cortex of Klf11(+/+) mice exposed to EtOH compared with control Klf11(+/+) mice. Furthermore, MAO enzyme activities were affected differently in Klf11 wild-type versus Klf11 knockout mice exposed to chronic EtOH. Chronic EtOH intake significantly increased MAO B activity in Klf11(+/+) mice. CONCLUSIONS: The data show KLF11 modulation of EtOH-induced antinociception. The KLF11-targeted MAO B enzyme may contribute more significantly to EtOH-induced antinociception. Thus, this study revealed a new role for the KLF11 gene in the mechanisms underlying the antinociceptive effects of chronic EtOH exposure.


Subject(s)
Alcoholism/genetics , Alcoholism/psychology , Analgesics , Central Nervous System Depressants/pharmacology , DNA-Binding Proteins/physiology , Diabetes Mellitus/genetics , Ethanol/pharmacology , Nociception/drug effects , Transcription Factors/physiology , Animals , Apoptosis Regulatory Proteins , Blotting, Western , DNA-Binding Proteins/biosynthesis , DNA-Binding Proteins/genetics , Male , Mice , Mice, Knockout , Monoamine Oxidase/genetics , Monoamine Oxidase/metabolism , Pain Measurement/drug effects , Prefrontal Cortex/drug effects , Prefrontal Cortex/enzymology , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Reaction Time/drug effects , Real-Time Polymerase Chain Reaction , Repressor Proteins , Transcription Factors/biosynthesis , Transcription Factors/genetics
13.
J Biol Chem ; 289(5): 2946-59, 2014 Jan 31.
Article in English | MEDLINE | ID: mdl-24324264

ABSTRACT

Apolipoprotein E4 (apoE4) allele is the major genetic risk factor for sporadic Alzheimer disease (AD) due to the higher prevalence and earlier onset of AD in apoE4 carriers. Accumulating data suggest that the interaction between the N- and the C-terminal domains in the protein may be the main pathologic feature of apoE4. To test this hypothesis, we used Arg-61 mice, a model of apoE4 domain interaction, by introducing the domain interaction feature of human apoE4 into native mouse apoE. We carried out hippocampus-dependent learning and memory tests and related cellular and molecular assays on 12- and 3-month-old Arg-61 and age-matched background C57BL/6J mice. Learning and memory task performance were impaired in Arg-61 mice at both old and young ages compared with C57BL/6J mice. Surprisingly, young Arg-61 mice had more mitotic doublecortin-positive cells in the subgranular zone; mRNA levels of brain-derived neurotrophic factor (BDNF) and TrkB were also higher in 3-month-old Arg-61 hippocampus compared with C57BL/6J mice. These early-age neurotrophic and neurogenic (proliferative) effects in the Arg-61 mouse may be an inadequate compensatory but eventually detrimental attempt by the system to "repair" itself. This is supported by the higher cleaved caspase-3 levels in the young animals that not only persisted, but increased in old age, and the lower levels of doublecortin at old age in the hippocampus of Arg-61 mice. These results are consistent with human apoE4-dependent cognitive and neuro-pathologic changes, supporting the principal role of domain interaction in the pathologic effect of apoE4. Domain interaction is, therefore, a viable therapeutic/prophylactic target for cognitive impairment and AD in apoE4 subjects.


Subject(s)
Aging/pathology , Alzheimer Disease/pathology , Apolipoprotein E4/metabolism , Cognition Disorders/pathology , Memory Disorders/pathology , Neurogenesis/physiology , Animals , Apolipoprotein E4/chemistry , Apolipoprotein E4/genetics , Brain-Derived Neurotrophic Factor/metabolism , Caspase 3/metabolism , Disease Models, Animal , Doublecortin Domain Proteins , Humans , Maze Learning , Mice , Mice, Inbred C57BL , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Neuropeptides/genetics , Neuropeptides/metabolism , Protein Structure, Tertiary , Receptor, trkB/metabolism
14.
Alcohol Clin Exp Res ; 38(1): 144-51, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23915421

ABSTRACT

BACKGROUND: The biochemical pathways underlying alcohol abuse and dependence are not well understood, although brain cell loss and neurotoxicity have been reported in subjects with alcohol dependence. Monoamine oxidase B (MAO B; an enzyme that catabolizes neurotransmitters such as dopamine) is consistently increased in this psychiatric illness. MAO B has been implicated in the pathogenesis of alcohol dependence and alcohol-induced brain neurotoxicity. Recently, the cell growth inhibitor protein, Kruppel-like factor 11 (KLF11), has been reported to be an MAO transcriptional activator. KLF11 is also known as TIEG2 (transforming growth factor-beta-inducible early gene 2) and mediates apoptotic cell death. This study investigates the protein expression of KLF11 and its relationship with MAO B using human postmortem prefrontal cortex from subjects with alcohol dependence. METHODS: Twelve subjects with alcohol dependence and the respective psychiatrically normal control subjects were investigated. Expression of KLF11 and MAO B proteins in the prefrontal cortex was measured by Western blot analysis. Correlation studies involving KLF11 and MAO B protein expression were performed. Localization of KLF11 in the human prefrontal cortex was also determined by immunohistochemistry. RESULTS: Levels of KLF11 protein were significantly increased by 44% (p < 0.03) in the postmortem prefrontal cortex of subjects with alcohol dependence as compared to age- and gender-matched, psychiatrically normal control subjects. Furthermore, KLF11 levels were significantly and positively correlated with both the increased MAO B protein levels and blood alcohol content in alcohol-dependent subjects. In addition, KLF11 protein expression was visualized in both neuronal and glial cells. CONCLUSIONS: This novel study shows the important role of KLF11, an MAO transcriptional activator, in human alcohol dependence. It further supports that the KLF11-MAO B cell death cascade may contribute to chronic alcohol-induced brain damage. This argues a case for KLF11-MAO B inhibition as a novel therapeutic strategy that may impact this highly prevalent illness.


Subject(s)
Alcoholism/metabolism , Cell Cycle Proteins/biosynthesis , Gene Expression Regulation , Monoamine Oxidase/biosynthesis , Prefrontal Cortex/metabolism , Repressor Proteins/biosynthesis , Transcriptional Activation/physiology , Alcoholism/pathology , Apoptosis Regulatory Proteins , Female , Humans , Male , Middle Aged , Prefrontal Cortex/pathology , Retrospective Studies
15.
Neuropsychopharmacology ; 39(4): 973-80, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24154665

ABSTRACT

Inadequate treatment response occurs in approximately 40% of major depressive episodes (MDEs), and one approach to solve this is careful matching of treatment to the specific pathologies of MDE. One such biological abnormality is elevated monoamine oxidase A (MAO-A) levels, which occurs in the prefrontal and anterior cingulate cortex (PFC and ACC) during MDE; however, the subtypes for which this abnormality is most prominent are unknown. We hypothesized that MAO-A levels in the PFC and ACC are most elevated in MDE with greater severity and reversed neurovegetative symptoms (hypersomnia and either hyperphagia or weight gain). MAO-A VT (an index of MAO-A density) was measured using [(11)C]harmine positron emission tomography (PET) in 42 subjects with MDEs secondary to major depressive disorder and 37 healthy controls. The effect of severity and reversed neurovegetative symptoms on MAO-A VT in the PFC and ACC was analyzed using a multivariate analysis of variance (MANOVA). Greater severity and reversed neurovegetative symptoms were associated with elevated MAO-A VT in the PFC and ACC (MANOVA, severity: F(2,38)=5.44, p=0.008; reversed neurovegetative symptoms: F(2,38)=5.13, p=0.01). Increased MAO-A level, when greater severity and reversed neurovegetative symptoms are present, may explain the association of these clinical features with a preferential response to MAO inhibitors, which is especially well-evidenced for reversed neurovegetative symptoms in MDE. As MAO-A creates oxidative stress, facilitates apoptosis, and metabolizes monoamines, therapeutics opposing these processes are predicted to best treat MDE with greater severity and reversed neurovegetative symptoms.


Subject(s)
Depressive Disorder, Major/complications , Disorders of Excessive Somnolence/etiology , Hyperphagia/etiology , Monoamine Oxidase/metabolism , Adult , Carbon Radioisotopes/pharmacokinetics , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/drug effects , Depressive Disorder, Major/classification , Depressive Disorder, Major/diagnostic imaging , Disorders of Excessive Somnolence/diagnostic imaging , Female , Harmine/pharmacokinetics , Humans , Hyperphagia/diagnostic imaging , Magnetic Resonance Imaging , Male , Monoamine Oxidase Inhibitors/pharmacokinetics , Positron-Emission Tomography , Protein Binding/drug effects , Protein Binding/physiology , Psychiatric Status Rating Scales , Severity of Illness Index , Statistics, Nonparametric , Young Adult
16.
J Chromatogr A ; 1318: 251-6, 2013 Nov 29.
Article in English | MEDLINE | ID: mdl-24354006

ABSTRACT

A microchip electrophoresis-mass spectrometric (MCE-MS) method was developed for fast chiral analysis. The proposed MCE-MS platform deployed a glass/PDMS hybrid microchip with an easy-to-fabricate monolithic nanoelectrospray emitter. Enantiomeric MCE separation was achieved by means of the partial filling technique. A novel chip design with an arm channel connecting to the middle of the MCE separation channel for delivering the chiral selector was tested and proven valid. Enantiomeric separation of3.4-dihydroxyphenylalanine (DOPA), glutamic acid (Glu), and serine (Ser), the selected test compounds,were achieved within 130 s with resolution values (R(s)) of 2.4, 1.1, and 1.0, respectively. The proposed chiral MCE-MS assay was sensitive and had detection limits of 43 nM for l-DOPA and 47 nM for d-DOPA.The analytical platform was well suited for studies of stereochemical preference in living cells because it integrated cell culture, sample injection, chiral separation, and MS detection into a single platform.Metabolism of DOPA in human SH-SY5Y neuronal cells was studied as a model system. On-chip incubation of SH-SY5Y cells with racemic DOPA was carried out, and the incubation solution was injected and in-line assayed at time intervals. It was found that l-DOPA concentration decreased gradually as incubation time increased while the concentration of coexisting d-DOPA remained constant. The results firmly indicated that SH-SY5Y cells metabolized l-DOPA effectively while left d-DOPA intact.


Subject(s)
Dihydroxyphenylalanine/chemistry , Electrophoresis, Microchip/methods , Glutamic Acid/chemistry , Mass Spectrometry/methods , Serine/chemistry , Cell Line , Cells/chemistry , Cells/metabolism , Dihydroxyphenylalanine/metabolism , Humans , Stereoisomerism
17.
Metab Brain Dis ; 28(4): 667-76, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23979425

ABSTRACT

Fetal alcohol spectrum disorders (FASD) results from ethanol exposure to the developing fetus and is the leading cause of mental retardation. FASD is associated with a broad range of neurobehavioral deficits which may be mediated by ethanol-induced neurodegeneration in the developing brain. An immature brain is more susceptible to ethanol neurotoxicity. We hypothesize that the enhanced sensitivity of the immature brain to ethanol is due to a limited capacity to alleviate cellular stress. Using a third trimester equivalent mouse model of ethanol exposure, we demonstrated that subcutaneous injection of ethanol induced a wide-spread neuroapoptosis in postnatal day 4 (PD4) C57BL/6 mice, but had little effect on the brain of PD12 mice. We analyzed the expression profile of genes regulating apoptosis, and the pathways of ER stress response (also known as unfolded protein response, UPR) and autophagy during these ethanol-sensitive and resistant periods (PD4 versus PD12) using PCR microarray. The expression of pro-apoptotic genes, such as caspase-3, was much higher on PD4 than PD12; in contrast, the expression of genes that regulate UPR and autophagy, such as atf6, atg4, atg9, atg10, beclin1, bnip3, cebpb, ctsb, ctsd, ctss, grp78, ire1α, lamp, lc3 perk, pik3c3, and sqstm1 was significantly higher on PD12 than PD4. These results suggest that the vulnerability of the immature brain to ethanol could result from high expression of pro-apoptotic proteins and a deficiency in the stress responsive system, such as UPR and autophagy.


Subject(s)
Autophagy/genetics , Brain/metabolism , Ethanol/pharmacology , Gene Expression Regulation, Developmental/drug effects , Unfolded Protein Response/genetics , Animals , Autophagy/drug effects , Brain/drug effects , Brain/growth & development , Caspase 3/genetics , Caspase 3/metabolism , Endoplasmic Reticulum Chaperone BiP , Mice , Mice, Inbred C57BL , Neurons/drug effects , Neurons/metabolism , Signal Transduction/drug effects , Unfolded Protein Response/drug effects
18.
Chem Biodivers ; 10(4): 600-11, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23576346

ABSTRACT

Twenty new trichodermin derivatives, 2a-5, containing alkoxy, acyloxy, and Br groups in 4-, 8-, 9-, 10- and 16-positions were synthesized and characterized. The antifungal activities of the new compounds against rice false smut (Ustilaginoidea virens), rice sheath blight (Rhizoctonia solani), and rice blast (Magnaporthe grisea) were evaluated. The results of bioassays indicated that the antifungal activities were particularly susceptible to changes at 4-, 8-, and 16-positions, but low to changes at 9- and 10-positions. Most of these target compounds exhibited good antifungal activities at the concentration of 50 mg l(-1) . Compound 4 (9-formyltrichodermin; EC50 0.80 mg l(-1) ) with an CHO group at 9-position displayed nearly the same level of antifungal activity against Ustilaginoidea virens as the commercial fungicide prochloraz (EC50 0.82 mg l(-1) ), while compound 3f ((8R)-8-{[(E)-3-phenylprop-2-enoyl]oxy}trichodermin; EC50 3.58 and 0.74 mg l(-1) ) with a cinnamyloxy group at C(8) exhibited much higher antifungal activities against Rhizoctonia solani and Magnaporthe grisea than the commercial fungicides prochloraz (EC50 0.96 mg l(-1) ) and propiconazole (EC50 5.92 mg l(-1) ), respectively. These data reveal that compounds 3f and 4 possess high antifungal activities and may serve as lead compounds for the development of fungicides in the future.


Subject(s)
Antifungal Agents/chemical synthesis , Trichodermin/chemistry , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Hypocreales/drug effects , Magnaporthe/drug effects , Oryza/microbiology , Plant Diseases/microbiology , Rhizoctonia/drug effects , Structure-Activity Relationship , Triazoles/pharmacology , Trichodermin/chemical synthesis , Trichodermin/pharmacology
19.
J Pain ; 14(6): 549-57, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23602266

ABSTRACT

UNLABELLED: Epigenetic regulation of gene expression is a rapidly growing area of research. Considering the longevity and plasticity of neurons, the studies on epigenetic pathways in the nervous system should be of special interest for both epigeneticists and neuroscientists. Activation or inactivation of different epigenetic pathways becomes more pronounced when the cells experience rapid changes in their environment, and such changes can be easily caused by injury and inflammation, resulting in pain perception or distortion of pain perception (eg, hyperalgesia). Therefore, in this regard, the field of pain is at an advantage to study the epigenetic pathways. More importantly, understanding pain from an epigenetics point of view would provide a new paradigm for developing drugs or strategies for pain management. In this review, we introduce basic concepts of epigenetics, including chromatin dynamics, histone modifications, DNA methylation, and RNA-induced gene silencing. In addition, we provide evidence from published studies suggesting wide implication of different epigenetic pathways within pain pathways. PERSPECTIVE: This article provides a brief overview of epigenetic pathways for gene regulation and highlights their involvement in pain. Our goal is to expose the readers to these concepts so that pain-related phenotypes can be investigated from the epigenetic point of view.


Subject(s)
Epigenesis, Genetic , Pain Management , Pain , Humans , Pain/diagnosis , Pain/genetics , Pain/pathology
20.
J Neurosci ; 32(48): 17120-7, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23197705

ABSTRACT

Monoamine oxidase-A (MAO-A), a key brain enzyme which metabolizes monoamines, is implicated in the pathophysiology of stress-related illnesses, including major depressive disorder, addiction, and violent behavior. Chronic stressors and glucocorticoid-administration typically associate with elevated MAO-A levels/activity. However, the relationship of shorter stress or glucocorticoid exposures and MAO-A levels/activity is not well established. Our objectives are to assess effects of acute stress upon MAO-A V(T,) an index of MAO-A density, in human brain and acute glucocorticoid exposure upon MAO-A levels in human neuronal and glial cell lines. Twelve healthy, non-smoking participants aged 18-50 underwent [(11)C]harmine positron emission tomography to measure brain MAO-A V(T) on two different days: One under acute psychosocial stress (via Trier Social Stress and Montreal Imaging Stress Tasks) and one under a non-stress condition. MAO-A density (by Western blot) and activity (by [(14)C]-5-HT metabolism and liquid scintillation spectroscopy) were measured in human neuronal and glial cell lines after 4 h exposure to dexamethasone. We observed a significant reduction in whole-brain MAO-A binding as reflected by reductions in 10 of 11 brain regions. Acute dexamethasone exposure in neuronal and glial cells significantly decreased MAO-A activity and protein levels. We observed a highly consistent relationship between acute stressors and glucocorticoid administration and decreased MAO-A binding, activity and protein levels. Since MAO-A metabolizes monoamines, this phenomenon may explain why acute stressors benefit healthy animals even though chronic stress is associated with illness.


Subject(s)
Brain/metabolism , Dexamethasone/pharmacology , Glucocorticoids/pharmacology , Monoamine Oxidase/metabolism , Stress, Psychological/metabolism , Adult , Brain/diagnostic imaging , Brain/drug effects , Cell Line, Tumor , Female , Humans , Hydrocortisone/blood , Male , Middle Aged , Neuroglia/drug effects , Neuroglia/metabolism , Neurons/drug effects , Neurons/metabolism , Radionuclide Imaging , Stress, Psychological/diagnostic imaging
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