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1.
Brain Stimul ; 17(3): 687-697, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38821397

ABSTRACT

BACKGROUND: Dopaminergic neurons in the ventral tegmental area (VTA) are crucially involved in regulating arousal, making them a potential target for reversing general anesthesia. Electrical deep brain stimulation (DBS) of the VTA restores consciousness in animals anesthetized with drugs that primarily enhance GABAA receptors. However, it is unknown if VTA DBS restores consciousness in animals anesthetized with drugs that target other receptors. OBJECTIVE: To evaluate the efficacy of VTA DBS in restoring consciousness after exposure to four anesthetics with distinct receptor targets. METHODS: Sixteen adult Sprague-Dawley rats (8 female, 8 male) with bipolar electrodes implanted in the VTA were exposed to dexmedetomidine, fentanyl, ketamine, or sevoflurane to produce loss of righting, a proxy for unconsciousness. After receiving the dopamine D1 receptor antagonist, SCH-23390, or saline (vehicle), DBS was initiated at 30 µA and increased by 10 µA until reaching a maximum of 100 µA. The current that evoked behavioral arousal and restored righting was recorded for each anesthetic and compared across drug (saline/SCH-23390) condition. Electroencephalogram, heart rate and pulse oximetry were recorded continuously. RESULTS: VTA DBS restored righting after sevoflurane, dexmedetomidine, and fentanyl-induced unconsciousness, but not ketamine-induced unconsciousness. D1 receptor antagonism diminished the efficacy of VTA stimulation following sevoflurane and fentanyl, but not dexmedetomidine. CONCLUSIONS: Electrical DBS of the VTA restores consciousness in animals anesthetized with mechanistically distinct drugs, excluding ketamine. The involvement of the D1 receptor in mediating this effect is anesthetic-specific.

2.
Behav Pharmacol ; 35(4): 156-160, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38651975

ABSTRACT

Exposure to chronic caffeine during adolescence has been shown to produce decreased anxiety-like behaviors in rats as well as decreased immobility in the forced swim test (FST) suggesting an antidepressant-like effect. The effects of chronic caffeine on anxiety, however, have been found to be test-dependent and sexually dimorphic. In addition, decreased immobility in the FST has been argued to reflect a shift toward active coping behavior as opposed to an antidepressant-like effect. In order to further characterize the effects of adolescent caffeine exposure, the present experiment assessed the effects of caffeine on marble burying behavior in a two-zone marble burying task. There was no difference in the amount of time rats spent in the two zones failing to support a shift in coping strategy. Caffeine-exposed rats spent less time engaged in marble burying activity and buried slightly fewer marbles, suggesting an anxiolytic effect of caffeine. In addition, caffeine treated rats spent less time engaged in nondirected burying and slightly more time actively engaging with the marbles; however, these effects appeared to be sexually dimorphic as they were driven by larger changes in the females. Overall, these results support an anxiolytic effect of adolescent caffeine, with female behavior appearing to be more affected by caffeine than males.


Subject(s)
Anxiety , Behavior, Animal , Caffeine , Animals , Caffeine/pharmacology , Caffeine/administration & dosage , Male , Anxiety/drug therapy , Female , Rats , Behavior, Animal/drug effects , Central Nervous System Stimulants/pharmacology , Anti-Anxiety Agents/pharmacology , Rats, Sprague-Dawley , Motor Activity/drug effects
3.
Chem Commun (Camb) ; 57(81): 10500-10503, 2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34580686

ABSTRACT

The movement of the sulfur species of a lithium-sulfur battery cathode was directly observed through pioneering operando SAXS analysis. Micropore is a prior repository for sulfur before and after the electrochemical reaction. Mesopore is actual reaction site for sulfur species. The separate properties of the pores were established, adding critical insight to advanced carbon cathode material design.

4.
Molecules ; 23(9)2018 Aug 23.
Article in English | MEDLINE | ID: mdl-30142905

ABSTRACT

Production of oligosaccharides from Leuconostoc lactis CCK940 was optimized using a response surface methodology with a central composite design. Culture temperature and the concentrations of sucrose and maltose were used as the main factors. The predicted optimum conditions for the production of oligosaccharides were a culture temperature of 30 °C, a sucrose concentration of 9.6% (w/v), and a maltose concentration of 7.4% (w/v). Using these optimal conditions, Leuconostoc lactis CCK940 was cultured using a fermenter to produce oligosaccharides, and the resulting oligosaccharides with a degree of polymerization greater than 4 were purified by Bio-gel P2 gel permeation column chromatography and then lyophilized. When macrophages were treated with the purified oligosaccharides at concentrations of 0.1⁻10 mg/mL, no cytotoxicity towards the macrophages was observed. However, nitric oxide production levels were similar to those following treatment with 1 µg/mL lipopolysaccharide. The mRNA expression levels of tumor necrosis factor-α, interleukin-1ß, interleukin-6, and inducible nitric oxide synthase were all also increased in a dose-dependent manner following treatment with the oligosaccharides. These data suggest that oligosaccharides produced by Leuconostoc lactis CCK940 could be used as an immune enhancer of macrophages.


Subject(s)
Leuconostoc/metabolism , Macrophages/drug effects , Oligosaccharides/metabolism , Oligosaccharides/pharmacology , Animals , Cell Survival/drug effects , Interleukin-1beta/genetics , Interleukin-6/genetics , Macrophages/metabolism , Mice , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Nitrogen Oxides/metabolism , RAW 264.7 Cells , RNA, Messenger/genetics , Temperature , Tumor Necrosis Factor-alpha/genetics
5.
ACS Nano ; 12(3): 2909-2921, 2018 03 27.
Article in English | MEDLINE | ID: mdl-29480713

ABSTRACT

Current lithium ion battery technology is tied in with conventional reaction mechanisms such as insertion, conversion, and alloying reactions even though most future applications like EVs demand much higher energy densities than current ones. Exploring the exceptional reaction mechanism and related electrode materials can be critical for pushing current battery technology to a next level. Here, we introduce an exceptional reaction with a Co(OH)2 material which exhibits an initial charge capacity of 1112 mAh g-1, about twice its theoretical value based on known conventional conversion reaction, and retains its first cycle capacity after 30 cycles. The combined results of synchrotron X-ray diffraction and X-ray absorption spectroscopy indicate that nanosized Co metal particles and LiOH are generated by conversion reaction at high voltages, and Co xH y, Li2O, and LiH are subsequently formed by hydride reaction between Co metal, LiOH, and other lithium species at low voltages, resulting in a anomalously high capacity beyond the theoretical capacity of Co(OH)2. This is further corroborated by AIMD simulations, localized STEM, and XPS. These findings will provide not only further understanding of exceptional lithium storage of recent nanostructured materials but also valuable guidance to develop advanced electrode materials with high energy density for next-generation batteries.

6.
Small ; 14(43): e1702985, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29280277

ABSTRACT

Nanostructured materials make a considerable impact on the performance of lithium-storage characteristics in terms of the energy density, power density, and cycle life. Direct experimental observation, by a comparison of controlled nanostructural uniformity of electrode materials, reveals that the lithium-storage behaviors of mesoporous MoO2 and CuO electrodes are linearly correlated with their nanostructural uniformity. Reversible capacities of mesoporous MoO2 and CuO electrodes with well-developed nanostructures (1569 mA h g-1 for MoO2 and 1029 mA h g-1 for CuO) exceed their theoretical capacity based on the conversion reaction (838 mA h g-1 for MoO2 and 674 mA h g-1 for CuO). Given that exact understanding of the origin of the additional capacity is essential in maximizing the energy density of electrode material, this work may help to gain some insights into the development of high energy-density lithium-storage materials for next-generation lithium rechargeable batteries.

7.
Chem Commun (Camb) ; 53(95): 12786-12789, 2017 Nov 28.
Article in English | MEDLINE | ID: mdl-29139485

ABSTRACT

(Hetero)aryloxytetrafluoroethylation of heteroaromatics and alkenes has been achieved by visible-light photocatalysis utilizing readily synthesized oxyfluoroalkyl reagents. The mild reaction conditions and the high diversity on both substrates and oxyfluoroalkyl reagents make this a useful method for late-stage modifications in the development of various functional molecules.

8.
Molecules ; 22(8)2017 Aug 08.
Article in English | MEDLINE | ID: mdl-28786926

ABSTRACT

For the fermentation of vinegar using onion, acetic acid bacteria and yeast strains with high fermentation ability were screened. Among them, Saccharomyces cerevisiae 1026 was selected as a starter for ethanol production and Acetobacter orientalis MAK88 was selected as a vinegar producer. When the two-stage fermentation of onion vinegar was performed at 28 °C, the titratable acidity reached 4.80% at 24 h of fermentation. When semi-continuous fermentation proceeded to charge-discharge consisting of three cycles, the acetic acid content reached 4.35% at 48 h of fermentation. At this stage, the fermentation efficiency, acetic acid productivity, and specific product formation rate were 76.71%, 17.73 g/(L·d), and 20.58 g/(g·h), respectively. The process in this study significantly reduced the fermentation time and simplified the vinegar production process. The content of total flavonoids and total polyphenols in onion vinegar were 104.36 and 455.41 µg/mL, respectively. The antioxidant activities of onion vinegar in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS⁺) radical scavenging activity, and reducing power were 75.33%, 98.88%, and 1.28, respectively. The nitrite scavenging abilities of onion vinegar were 95.38 at pH 1.2. The onion vinegar produced in this study showed higher organoleptic acceptability than commercial onion vinegar.


Subject(s)
Acetic Acid/chemistry , Acetic Acid/metabolism , Fermentation , Onions/metabolism , Acetic Acid/analysis , Acetic Acid/pharmacology , Antioxidants/analysis , Antioxidants/chemistry , Bacteria/metabolism , Bioreactors , Biphenyl Compounds/antagonists & inhibitors , Biphenyl Compounds/chemistry , Ethanol/metabolism , Flavonoids/analysis , Flavonoids/chemistry , Food Microbiology , Nitrites/antagonists & inhibitors , Nitrites/chemistry , Picrates/antagonists & inhibitors , Picrates/chemistry , Polyphenols/analysis , Polyphenols/chemistry , Saccharomyces cerevisiae/metabolism , Workflow
9.
Biol Pharm Bull ; 40(6): 932-935, 2017.
Article in English | MEDLINE | ID: mdl-28566637

ABSTRACT

We previously reported that the extract of Cinnamomum loureirii (C. loureirii) significantly inhibited acetylcholinesterase (AChE), and identified 2,4-bis(1,1-dimethylethyl)phenol (BP) from C. loureirii as a potential AChE inhibitor. The present study, therefore was undertaken to demonstrate the effects of BP from C. loureirii on learning and memory impairment in trimethyltin (TMT)-treated ICR mice. Y-maze and passive avoidance tests were used to test cognitive ability. Further, changes in biochemical parameters in the brain tissue were also assessed in response to TMT injection and BP intervention. BP pre-administration (20, 40 mg/kg/d) in mice significantly protected cognitive dysfunction induced by TMT (p<0.05). Moreover, BP reduced AChE activity and lipid peroxidation but increased acetylcholine levels in the brain. In conclusion, we suggested that BP protected against TMT-induced cognitive dysfunction, and might be a potential agent for alleviating symptoms of neurodegenerative disorders, such as Alzheimer's disease, via modulating cholinergic functions.


Subject(s)
Cinnamomum , Cognition Disorders/drug therapy , Memory Disorders/drug therapy , Neuroprotective Agents/therapeutic use , Phenols/therapeutic use , Acetylcholinesterase/metabolism , Animals , Brain/drug effects , Brain/metabolism , Cognition Disorders/chemically induced , Cognition Disorders/metabolism , Lipid Peroxidation/drug effects , Male , Maze Learning/drug effects , Memory Disorders/chemically induced , Memory Disorders/metabolism , Mice, Inbred ICR , Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Phenols/pharmacology , Trimethyltin Compounds
10.
Biol Pharm Bull ; 39(7): 1130-6, 2016.
Article in English | MEDLINE | ID: mdl-27374288

ABSTRACT

The pathogenesis of Alzheimer's disease (AD) has been linked to the deficiency of neurotransmitter acetylcholine (ACh) in the brain, and the main treatment strategy for improving AD symptoms is the inhibition of acetylcholinesterase (AChE) activity. In the present study, we aimed to identify potent AChE inhibitors from Cinnamomum loureirii extract via bioassay-guided fractionation. We demonstrated that the most potent AChE inhibitor present in the C. loureirii extract was 2,4-bis(1,1-dimethylethyl)phenol. To confirm the antiamnesic effects of the ethanol extract of C. loureirii, mice were intraperitoneally injected with the neurotoxin trimethyltin (2.5 mg/kg) to induce cognitive dysfunction, and performance in the Y-maze and passive avoidance tests was assessed. Treatment with C. loureirii extract significantly improved performance in both behavioral tests, suggesting that this extract may be neuroprotective and therefore beneficial in preventing or ameliorating the degenerative processes of AD, potentially by restoring cholinergic function.


Subject(s)
Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/therapeutic use , Cinnamomum , Cognitive Dysfunction/drug therapy , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Acetylcholinesterase/metabolism , Animals , Avoidance Learning/drug effects , Behavior, Animal/drug effects , Cell Line, Tumor , Cholinesterase Inhibitors/isolation & purification , Cognitive Dysfunction/chemically induced , Male , Maze Learning/drug effects , Mice, Inbred ICR , Neurotoxins , Phenols/isolation & purification , Phenols/pharmacology , Phenols/therapeutic use , Phytotherapy , Plant Extracts/chemistry , Rats , Trimethyltin Compounds
11.
Springerplus ; 5: 413, 2016.
Article in English | MEDLINE | ID: mdl-27069833

ABSTRACT

BACKGROUND: Cytochrome P450 (CYP) isoenzymes are an important phase I enzyme system. In the present study, we investigated the effects of Oenanthe javanica (Blume) DC on CYP1A1 and CYP1A2. FINDINGS: Whole plants were completely dried and then divided into leaves, stems, and roots for extraction. The human liver hepatocellular carcinoma cell line HepG2 was treated with ethanol extracts of these organs for 72 h and mRNA and protein expression levels were assessed. The root extract of O. javanica significantly elevated the expression of both CYP1A1 and CYP1A2 mRNAs (by 68 and 102 %, respectively). Similarly, the CYP1A1 and CYP1A2 protein levels were increased by the root extract (by 112 and 157 %, respectively). The effects of the root extract were much more pronounced than those of leaf and stem extracts. Subsequent GC-MS analysis revealed that the levels of major coumarin derivatives, xanthotoxin, bergapten, and isopimpinellin, were significantly higher in O. javanica root extracts than in leaf or stem extracts. Of note, 5 µM xanthotoxin (the most abundant furanocoumarin in O. javanica) induced the expression of CYP1A1 mRNA as well as CYP1A2 mRNA and protein, albeit the CYP1A1 protein level was elevated only at 10 µM xanthotoxin. CONCLUSIONS: Although it is difficult to extrapolate such effects to metabolic outcomes because of the inherent limitations of in vitro experiments, it is important to note that dietary exposure to O. javanica may modulate phase I enzymes and thereby affect various xenobiotic metabolism.

12.
Nat Commun ; 7: 11049, 2016 Mar 22.
Article in English | MEDLINE | ID: mdl-27001935

ABSTRACT

Developing electrode materials with high-energy densities is important for the development of lithium-ion batteries. Here, we demonstrate a mesoporous molybdenum dioxide material with abnormal lithium-storage sites, which exhibits a discharge capacity of 1,814 mAh g(-1) for the first cycle, more than twice its theoretical value, and maintains its initial capacity after 50 cycles. Contrary to previous reports, we find that a mechanism for the high and reversible lithium-storage capacity of the mesoporous molybdenum dioxide electrode is not based on a conversion reaction. Insight into the electrochemical results, obtained by in situ X-ray absorption, scanning transmission electron microscopy analysis combined with electron energy loss spectroscopy and computational modelling indicates that the nanoscale pore engineering of this transition metal oxide enables an unexpected electrochemical mass storage reaction mechanism, and may provide a strategy for the design of cation storage materials for battery systems.

13.
J Med Food ; 19(3): 281-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26505950

ABSTRACT

One of the critical features of Alzheimer's disease is cognitive dysfunction, which is, in part, due to decreases in acetylcholine (ACh). The ethanol extract of Perilla frutescens was selected for isolating the acetylcholinesterase (AChE) inhibitor based on preliminary screening. In vivo behavioral tests were performed to examine the effects of the P. frutescens extract on trimethyltin chloride-induced impairment of learning and memory in mice. A diet containing P. frutescens extract effectively reversed learning and memory impairment on the Y-maze and passive avoidance tests. To isolate the active compound from the P. frutescens extract, solvent partitioning, silica gel open column chromatography, thin-layer chromatography, and high-performance liquid chromatography were used. The AChE inhibitor was identified as rosmarinic acid.


Subject(s)
Acetylcholinesterase/metabolism , Alzheimer Disease/drug therapy , Cholinesterase Inhibitors/administration & dosage , Perilla frutescens/chemistry , Plant Extracts/administration & dosage , Trimethyltin Compounds/toxicity , Alzheimer Disease/enzymology , Alzheimer Disease/psychology , Animals , Cholinesterase Inhibitors/chemistry , Humans , Male , Maze Learning , Mice , Mice, Inbred ICR , Plant Extracts/chemistry
14.
Chem Pharm Bull (Tokyo) ; 63(12): 1076-80, 2015.
Article in English | MEDLINE | ID: mdl-26633030

ABSTRACT

The aim of this study was to search for a novel choline acetyltransferase (ChAT) activator from plants traditionally grown in Korea. An ethanol extract from Chaenomeles sinensis Koehne showed the highest ChAT-activating effect in vitro in an assay that used human neuroblastoma cells and [(14)C]acetyl-CoA. The active compound was speculated to be stearic acid methyl ester (SAME). In an in vivo experiment, C. sinensis extract and SAME improved trimethyltin (TMT)-induced deficits in learning and memory in mice as assessed by a Y-maze behavioral test and a passive avoidance test. The C. sinensis extract might attenuate the TMT-induced brain disorder. This study suggests that SAME from C. sinensis might be useful in the treatment of Alzheimer's disease.


Subject(s)
Choline O-Acetyltransferase/metabolism , Maze Learning/drug effects , Memory Disorders/drug therapy , Neuroblastoma/metabolism , Plant Extracts/pharmacology , Rosaceae/chemistry , Animals , Cell Line, Tumor , Enzyme Activation/drug effects , Humans , Male , Memory Disorders/chemically induced , Mice , Mice, Inbred ICR , Neuroblastoma/enzymology , Neuroblastoma/pathology , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Trimethyltin Compounds/pharmacology
15.
J Anal Methods Chem ; 2015: 916346, 2015.
Article in English | MEDLINE | ID: mdl-26550520

ABSTRACT

Few studies have investigated Seomae mugwort (a Korean native mugwort variety of Artemisia argyi H. Lév. & Vaniot), exclusively cultivated in the southern Korean peninsula, and the possibility of its use as a food resource. In the present study, we compared the nutritional and chemical properties as well as sensory attributes of Seomae mugwort and the commonly consumed species Artemisia princeps Pamp. In comparison with A. princeps, Seomae mugwort had higher contents of polyunsaturated fatty acids, total phenolic compounds, vitamin C, and essential amino acids. In addition, Seomae mugwort had better radical scavenging activity and more diverse volatile compounds than A. princeps as well as favorable sensory attributes when consumed as tea. Given that scant information is available regarding the Seomae mugwort and its biological, chemical, and sensory characteristics, the results herein may provide important characterization data for further industrial and research applications of this mugwort variety.

16.
J Nanosci Nanotechnol ; 15(3): 2441-5, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26413684

ABSTRACT

Ordered mesoporous MnO, MnO4, Mn2O3 and MnO2 materials with 3-D pore structure were suc- cessfully synthesized via a nano-replication method by using ordered mesoporous silica, KIT-6 (Cubic Ia3d space group mesostructure) as the template under specific oxidation and reduction conditions. Notably, ordered mesoporous MnO with a crystalline wall (rock salt structure) was syn- thesized for the first time, to the best of our knowledge. The synthesis of the ordered mesoporous MnO was achieved by reducing the ordered mesoporous Mn3O4 under an H2 atmosphere, while preserving the ordered mesostructure and crystalline wall throughout the solid/solid transformation. All of the ordered mesoporous manganese oxides with different crystal structures and oxidation states demonstrated almost the same spherical-like morphology with several hundred nanometers of particles. The synthesized ordered mesoporous manganese oxides had uniform dual mesopores (2-3 nm, and ~20 nm) and crystalline frameworks with large surface areas (86-140 m2/g) and pore volumes (0.27-0.33 cm3/g).


Subject(s)
Manganese Compounds/chemistry , Manganese Compounds/chemical synthesis , Oxides/chemistry , Oxides/chemical synthesis , Chemistry Techniques, Synthetic , Oxidation-Reduction , Porosity , Silicon Dioxide/chemistry
17.
ACS Nano ; 9(5): 5470-7, 2015 May 26.
Article in English | MEDLINE | ID: mdl-25869353

ABSTRACT

To monitor dynamic volume changes of electrode materials during electrochemical lithium storage and removal process is of utmost importance for developing high performance lithium storage materials. We herein report an in operando probing of mesoscopic structural changes in ordered mesoporous electrode materials during cycling with synchrotron-based small angel X-ray scattering (SAXS) technique. In operando SAXS studies combined with electrochemical and other physical characterizations straightforwardly show how porous electrode materials underwent volume changes during the whole process of charge and discharge, with respect to their own reaction mechanism with lithium. This comprehensive information on the pore dynamics as well as volume changes of the electrode materials will not only be critical in further understanding of lithium ion storage reaction mechanism of materials, but also enable the innovative design of high performance nanostructured materials for next generation batteries.

18.
J Med Food ; 17(11): 1222-31, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25133313

ABSTRACT

Alzheimer's disease (AD) is pathologically characterized by the presence of amyloid plaques in brain and the overproduction of amyloid beta (Aß), leading to learning and memory impairment and intense oxidative stress. In this study, the protective effect of Ligularia fischeri extract was investigated using PC12 cells. L. fischeri extract attenuated hydrogen-peroxide-induced DNA fragmentation in cells. In vivo behavioral tests were performed to examine the effects of the extract on amyloid-ß peptide1-42-induced impairment of learning and memory in mice. A diet containing the extract increased alternation behaviors in the Y-maze test and step-through latency of passive avoidance task. Moreover, we found that consumption of the extract decreased lipid peroxidation in a biochemical study of brain tissue in mice. High-performance liquid chromatography was used to identify the active compounds in the extract. These results suggest that L. fischeri extract could be protective against Aß-induced neurotoxicity, possibly due to the antioxidative capacity of its constituent, 3-O-caffeoylquinic acid.


Subject(s)
Amyloid beta-Peptides/metabolism , Antioxidants/therapeutic use , Asteraceae/chemistry , Brain/drug effects , DNA Fragmentation/drug effects , Neurotoxicity Syndromes/prevention & control , Oxidative Stress/drug effects , Alzheimer Disease/metabolism , Alzheimer Disease/prevention & control , Amyloid beta-Peptides/toxicity , Animals , Antioxidants/pharmacology , Avoidance Learning/drug effects , Chlorogenic Acid/pharmacology , Chlorogenic Acid/therapeutic use , Cognition Disorders/chemically induced , Cognition Disorders/genetics , Cognition Disorders/prevention & control , Hydrogen Peroxide/metabolism , Hydrogen Peroxide/toxicity , Learning Disabilities/chemically induced , Learning Disabilities/prevention & control , Lipid Peroxidation/drug effects , Male , Memory/drug effects , Memory Disorders/chemically induced , Memory Disorders/prevention & control , Mice, Inbred ICR , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Neurotoxicity Syndromes/genetics , PC12 Cells , Phytotherapy , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Rats
19.
Biosci Biotechnol Biochem ; 78(6): 981-8, 2014.
Article in English | MEDLINE | ID: mdl-25036123

ABSTRACT

Phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine (PC), the most abundant phospholipids of plasma membrane, resulting in the production of choline and phosphatidic acid (PA). Choline is a precursor of the neurotransmitter acetylcholine, whereas PA functions as an intracellular lipid mediator of diverse biological functions. For assessing PLD activity in vitro, PLD-derived choline has been often analyzed with radioactive or non-radioactive methods. In this study, we have developed a new method for detecting choline and PA with MALDI-QIT-TOF/MS by using 9-aminoacridine as a matrix. The standard calibration curves showed that choline and PA could be detected with linearity over the range from 0.05 and 1 pmol, respectively. Importantly, this method enables the concomitant detection of choline and PA as a reaction product of PC hydrolysis by PLD2 proteins. Thus, our simple and direct method would be useful to characterize the enzymatic properties of PLD, thereby providing insight into mechanisms of PLD activation.


Subject(s)
Aminacrine/metabolism , Biocatalysis , Choline/metabolism , Enzyme Assays/methods , Phosphatidic Acids/metabolism , Phospholipase D/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , HEK293 Cells , Humans , Hydrolysis , Limit of Detection
20.
Food Chem Toxicol ; 66: 341-9, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24525099

ABSTRACT

Atopic dermatitis (AD) is a multifactorial chronic skin disorder that is increasing in prevalence globally. In NC/Nga mice, repetitive epicutaneous applications of 2-4-dinitrofluorobenzene (DNFB) induces AD-like clinical symptoms. Bioflanonol fisetin (3,7,3',4'-tetrahydroxyflavone) is a dietary component found in plants, fruits and vegetables. Fisetin has various physiological effects that include anti-oxidation, anti-angiogenesis, anti-carcinogenesis and anti-inflammation. In this study, we investigated whether fisetin relieves AD-like clinical symptoms induced by repeated DNFB treatment in NC/Nga mice. Fisetin significantly inhibited infiltration of inflammatory cells including eosinophils, mast cells and CD4(+) T and CD8(+) T cells, and suppressed the expressions of cytokines and chemokines associated with dermal infiltrates in AD-like skin lesions. Total serum immunoglobulin E (IgE) levels and the ratio of phospho-NF-κB p65 to total NF-κB p65 were markedly reduced by fisetin. Fisetin also reduced the production of interferon-gamma and interleukin-4 by activated CD4(+) T cells in a dose-dependent manner, whereas the anti-inflammatory cytokine, interleukin-10 was increased. These results implicate fisetin as a potential therapeutic for AD.


Subject(s)
Dermatitis, Atopic/etiology , Dinitrofluorobenzene/toxicity , Flavonoids/pharmacology , Immunosuppressive Agents/pharmacology , Animals , Base Sequence , CD4-Positive T-Lymphocytes/metabolism , DNA Primers , Flavonols , Immunoglobulin E/blood , Male , Mice , Polymerase Chain Reaction
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