• BMB Reports
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• v.31 no.3
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• pp.254-257
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• 1998

The gshI gene from the Escherichia coli K-12 strain codes for ${\gamma}-glutamylcysteine$ synthetase which mediates the rate-limiting step of glutathione biosynthesis. The isolated gshI gene from E. coli K-12 has an unusual translation initiation codon, UUG. The 494th amino acid is Ala rather than Gly which was found in a mutant strain E. coli B. In order to improve the translational rate of the gshI gene of E. coli K-12, the initiation codon, UUG, was changed to the usual AUG codon by the site-specific mutagenesis. This change has resulted in a 53% increase of ${\gamma}-glutamylcysteine$ synthetase activity. The enzyme activity was also improved by replacing $Ala^{494}$ with Val (A494V) or Leu (A494L). The replacement of $Ser^{495}$ with Thr (S495T) also resulted in a 62% increase of the enzyme activity. Therefore, the specific activity of ${\gamma}-glutamylcysteine$ synthetase was increased with the increasing chain length of the aliphathic amino acid at the site of the 494th amino acid (Ala<$Val{\leq}Leu$).

• The Plant Pathology Journal
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• v.29 no.1
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• pp.110-115
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• 2013

Theobroxide, a novel compound isolated from a fungus Lasiodiplodia theobromae, stimulates potato tuber formation and induces flowering of morning glory by initiating the jasmonic acid synthesis pathway. To elucidate the effect of theobroxide on pathogen resistance in plants, Nicotiana benthamiana plants treated with theobroxide were immediately infiltrated with Pseudomonas syringae pv. tabaci. Exogenous application of theobroxide inhibited development of lesion symptoms, and growth of the bacterial cells was significantly retarded. Semiquantitative RT-PCRs using the primers of 18 defense-related genes were performed to investigate the molecular mechanisms of resistance. Among the genes, the theobroxide treatment increased the expression of patho-genesis-related protein 1a (PR1a), pathogenesis-related protein 1b (PR1b), glutathione S-transferase (GST), allen oxide cyclase (AOC), and lipoxyganase (LOX). All these data strongly indicate that theobroxide treatment inhibits disease development by faster induction of defense responses, which can be possible by the induction of defense-related genes including PR1a, PR1b, and GST triggered by the elevated jasmonic acid.

• Environmental Analysis Health and Toxicology
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• v.11 no.1_2
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• pp.41-47
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• 1996

1, 2, 4-Trichlorobenzene (1, 2, 4-TCB) is used as a dye carrier, as an intermediate in the synthesis of herbicides, as a flame retardant, and for other purpose. After a single oral administration of 1, 2, 4-TCB (200 mg/kg, 400 mg/kg) in rats, toxic effects were studied by means of serum biochemical and heatological analysis, and liver calcium concentration. Administration of 1, 2, 4-TCB resulted in dose-dependent liver and kidney damage as estimated by increased serum alanine aminotransferase (ALT) activities, liver calcium concentration and blood urea nitrogen (BUN). Pretreatment with DL-buthionine sulfoximine (BSO, 2 mmol/kg, i.p. ) considerably decreased liver glutathione concentration, which was accompanied by markedly elevated serum ALT activites. It is well-known that toxicity of halogenated benzene such as bromobenzene, 1, 4-dichlorobenzene is increased by pretreatment of henobarbital (PB), and protected by pretreatment of cytochrome P450 inhibitor including metyrapone (MP). However, there was no obvious alterations in toxicity of 1, 2, 4-TCB by pretreatment of phenobarbital or metyrapone. In comparison with control group, treatment groups exhibited significant changes in some parameters of hematological analysis but all hematological values remined within normal ranges.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.331-339
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• 2001

목적 : 본 연구는 식풍해경(熄風解痙), 소산풍열(疏散風熱) 효능이 있는 백강잠이 치매에 미치는 영향을 알아보기 위하여 실험을 행하였다. 방법 : 치매 유발물질인 $amyloid{\beta}(A{\beta})$ 25-35를 흰쥐의 뇌 astrocyte에 처리한 후 대표적인 항산화 효소인 catalase, superoxide dismutase,glutathione peroxidase 및 glutathione-S-transferase의 활성 변화와 NO 생성 변화를 관찰하였다. 결과 $A{\beta}$ 25-35 처리로 catalase와 superoxide dismutase 활성이 현저히 감소하였으나 백강잠을 처리한 경우는 이들 효소 활성이 크게 증가하였다. 그리고, $A{\beta}$ 25-35의 농도에 의존적으로 증가된 NO 생성은 백강잠의 농도에 의존적으로 유의성 있게 억제되는 것으로 나타났다. 결론 : 백강잠은 항산화계 효소의 활성화 및 $A{\beta}$처리와 같은 치매유발 물질의 독성에 대한 적응능력 향상을 통하여 astrocyte를 보호하는 효능을 가지는 것으로 사료되며, 아울러 노인성 치매 등 임상적 응용에 그 효과가 기대된다.

• Journal of Powder Materials
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• v.28 no.1
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• pp.44-50
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• 2021

Zinc selenide (ZnSe) nanoparticles were synthesized in aqueous solution using glutathione (GSH) as a ligand. The influence of the ligand content, reaction temperature, and hydroxyl ion concentration (pH) on the fabrication of the ZnSe particles was investigated. The optical properties of the synthesized ZnSe particles were characterized using various analytical techniques. The nanoparticles absorbed UV-vis light in the range of 350-400 nm, which is shorter than the absorption wavelength of bulk ZnSe particles (460 nm). The lowest ligand concentration for achieving good light absorption and emission properties was 0.6 mmol. The reaction temperature had an impact on the emission properties; photoluminescence spectroscopic analysis showed that the photo-discharge characteristics were greatly enhanced at high temperatures. These discharge characteristics were also affected by the hydroxyl ion concentration in solution; at pH 13, sound emission characteristics were observed, even at a low temperature of 25℃. The manufactured nanoparticles showed excellent light absorption and emission properties, suggesting the possibility of fabricating ZnSe QDs in aqueous solutions at low temperatures.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.157-163
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• 2012

Objective: Glutathione S-transferases (GSTs) are multifunctional enzymes that play a crucial role in the detoxification of both the endogenous products of oxidative stress and exogenous carcinogens. Recent studies investigating the association between genetic polymorphisms in GSTs and the risk of adult brain tumors have reported conflicting results. The rationale of this pooled analysis was to determine whether the presence of a GST variant increases adult glioma susceptibility by combining data from multiple studies. Methods: In our meta-analysis, 12 studies were identified by a search of the MEDLINE, HIGHWIRE, SCIENCEDIRECT and EMBASE databases. Of those 12, 11 evaluated GSTM1, nine evaluated GSTT1 and seven evaluated GSTP1 Ile105Val. Between-study heterogeneity was assessed using ${\chi}^2$-based Q statistic and the $I^2$ statistic. Crude odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to estimate the association between GSTM1, GSTT1 and GSTP1 polymorphisms and the risk of adult gliomas. Results: The quantitative synthesis showed no significant evidence to indicate an association exists between the presence of a GSTM1, GSTT1 or GSTP1 Ile105Val haplotype polymorphism and the risk of adult gliomas (OR, 1.008, 1.246, 1.061 respectively; 95% CI, 0.901-1.129, 0.963-1.611, 0.653-1.724 respectively). Conclusions: Overall, this study did not suggest any strong relationship between GST variants or related enzyme polymorphisms and an increased risk of adult gliomas. Some caveats include absence of specific raw information on ethnic groups or smoking history on glioma cases in published articles; therefore, well-designed studies with a clear stratified analysis on potential confounding factors are needed to confirm these results.

• Biomolecules & Therapeutics
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• v.13 no.4
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• pp.256-262
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• 2005

We examined the signaling molecules involved in the 6-hydroxydopamine (6-OHDA)-induced neuronal cell death and increase in cellular glutathione (GSH) level in SK-N-SH cells. The 6-OH-DA-induced cell death was significantly prevented by the pretreatment with N-acetylcysteine (NAC), a thiol antioxidant, and BAPTA, an intracellular $Ca^{2+}$ chelator. Although 6-OHDA induced ERK phosphorylation, the pretreatment with PD98059, an ERK inhibitor, did not block 6-OHDA-induced cell death. In addition, the 6-OHDA-induced activation of caspase-3, a key signal for apoptosis, was blocked by the pretreatment with NAC and BAPTA. While the level of reactive oxygen species (ROS) was significantly increased in the 6-OHDA-treated cells, the cellular GSH level was not altered for the first 6-hr exposure to 6-OHDA, but after then, the level was significantly increased, which was also blocked by the pretreatment with NAC and BAPTA, but not by PD98059. Depletion of GSH by pretreating the cells with DL-buthionine-(S,R)-sulfoximine (BSO), a glutathione synthesis inhibitor, rather significantly potentiated the 6-OHDA-induced death. In contrast to the pretreatment with NAC, 6-OHDA-induced cell death was not prevented by the post-treatment with NAC 30 min after 6-OHDA treatment. The results indicate that the GSH level which is increased adaptively by the 6-OHDA-induced ROS and intracellular $Ca^{2+}$ is not enough to overcome the death signal mediated through ROS-$Ca^{2+}$ -caspase pathway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.344-350
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• 1997

The present study was carried out to investigate the effects of zinc and vitamin E on the antioxidative defense mechanism in the liver of streptozotocin(STZ)-induced diabetic rats. Levels of blood glucose of STZ-diabetic rats were higher than that of control, but ZDM($ZnSO_{4}$ 10mg/kg injection+STZ) group was lower than those of DM(STZ injection) and EDM(vitamin E 400mg/kg diet+STZ) group. Levels of plasma insulin were lower in all three STZ-diabetic groups than those of control. Thiobarbituric acid reactive substances(TBARS) peroxide values(LPO) in liver were increased 2.3-fold in DM group compared with those of control, while LPG in ZDM group was lower than that of DM group, and EDM group had similar tendency compared with that of control. Reduced glutathione(GSH) contents of liver were decreased in DM group compared with those of control, but increased 2.3, 1.7-fold in ZDM and EDM groups, respectively, compared with those of DM group. Oxidized glutathione(GSSG) was increased in DM group compared with control and GSSG in ZDM and EDM group were lower than that of DM group. GSH/GSSG ratio had similar tendency compared with results of GSH. The activities of free radical scavenging enzymes such as superoxide dismutase, glutathione peroxidase and glutathione S-transferase were significantly decreased in DM group compared to those of control, but higher in ZDM and EDM groups than those of DM group. The metallothionein contents in liver and kidney were increased in DM and EDM groups were remarkably increased 20, 5.3-fold in ZDM group, compared with those of control.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.475-483
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• 1994

Background: N-acetylcysteine(ACE) is used both orally and intravenously in a variety of experimental pathologies resembling human disease states which exhibit endothelial toxicity as a result of oxidative stress, including acute pulmonary oxygen toxicity, septicemia and endotoxin shock. Despite these observations in vivo, it is not certain how this thiol drug produces its protective effects. ACE is a cysteine derivative which is able to direct1y react with oxygen radicals and may also act as a cysteine and glutathione(GSH) precursor following deacetylation. In this paper, we tried to know whether the therapeutic doses of ACE can modify the inflammatory function of the neutrophils and can increase the glutathione level of plasma in chronic obstructive pulmonary disease(COPD) patients. In addition, the effect of ACE to the purified neutrophil in terms of superoxide release and glutathione synthesis were observed. Method: Firstly, we gave 600mg of ACE for seven days and compare the release of superoxide, luminol-enhanced chemiluminescence from the neutrophils, neutrophil chemotaxis, and plasma GSH levels before and after ACE treatment in COPD patients. Secondly, we observed the dose dependent effect of ACE to the purified neutrophil's superoxide release and GSH levels in vitro. Results: 1) Usual oral therapeutic doses(600mg per day) of ACE for seven days did affect neither on the neutrophil's superoxide release, chemiluminescence, chemotaxis, nor on the plasma GSH concentration in the COPD patients. 2) ACE decreases the purified neutrophil's superoxide release and increase the GSH production in dose dependent fashion in vitro. Conclusion: Despite the fact that oral ACE treatment did not affect on the neutrophil's inflammatory function and plasma GSH concentration in COPD patients in usual therapeutic doses, it decreases the superoxide release and increases the GSH production from the isolated neutrophils in high molar concentrations. These findings suggest that to obtain an antioxidative effects of ACE, it might be needed to increase the daily dosage of ACE or therapeutic duration or change the route of adminisration in COPD patients.

• Molecules and Cells
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• v.20 no.1
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• pp.43-50
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• 2005

Glutaredoxin (Grx) is a small, heat-stable redox protein acting as a multi-functional glutathione (GSH)-dependent disulfide oxidoreductase. We have cloned the monothiol Grx5 gene from the genomic DNA of the fission yeast Schizosaccharomyces pombe. It has 1,904 bp, with one intron, and encodes a putative protein of 146 amino acids with a molecular mass of 16.5 kDa. Recombinant Grx5 produced functional Grx in S. pombe cells. NO-generating sodium nitroprusside (SNP, 1.0 and 2.0 mM) and potassium chloride (KCl, 0.2 and 0.5 M) increased the synthesis of ${\beta}$-galactosidase from a Grx5-lacZ fusion gene, and transcription of Grx5 was also enhanced by SNP and KCl. Synthesis of ${\beta}$-galactosidase from the Grx5-lacZ fusion was lower in Pap1-negative TP108-3C cells than in wild type KP1 cells, and when Pap1 was overproduced in KP1 cells, the level of ${\beta}$-galactosidase increased. We also found that Pap1 is involved in the induction of Grx5 by SNP and KCl. S. pombe Grx5 may play a crucial role in responses to nitrosative and osmotic stresses.