• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1065-1072
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• 2005

The nascent thyroglobulin (Tg) multimer molecule, which is generated during the initial fate of Tg in ER, undergoes the rapid reductive depolymerization. In an attempt to determine the depolymerization process, various types of Tg multimers, which were generated from deoxy­cholate-treated/reduced Tg, partially unfolded Tg or partially unfolded/reduced Tg, were subjected to various GSH (reduced glutathione) reducing systems using protein disulfide isomerase (PDI), glutathione reductase (GR), glutaredoxin or thioredoxin reductase. The Tg multimers generated from deoxycholate-treated/reduced Tg were depolymerized readily by the PDI/GSH system, which is consistent with the reductase activity of PDI. The PDI/GSH-induced depolymerization of the Tg multimers, which were generated from either partially unfolded Tg or partially unfolded/reduced Tg, required the simultaneous inclusion of glutathione reductase, which is capable of reducing glutathionylated mixed disulfide (PSSG). This suggests that PSSG was generated during the Tg multimerization stage or its depolymerization stage. In particular, the thioredoxin/thioredoxin reductase system or glutaredoxin system was also effective in depolymerizing the Tg multimers generated from the unfolded Tg. Overall, under the net GSH condition, the depolymerization of Tg multimers might be mediated by PDI, which is assisted by other reductive enzymes, and the mechanism for depolymerizing the Tg multimers differs according to the type of Tg multimer containing different degrees and types of disulfide linkages.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1582-1585
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• 2004

The antioxidative ability on the basis of reduced glutathione sulphydryl level, the inhibition activities of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and the effects of types of media and growth phase of the cells on the cellular GSH level have been determined. Correlation between reduced glutathione sulphydryl level and antioxidative ability of Lactobacillus spp. was analyzed: Lactobacillus casei HY 2782 contained 25.15 $\mu$mole/g of GSH, the cellular GSH level of L. casei HY 2782 reached maximum after 24 h of cultivation and tended to decrease on further cultivation up to 72 h. There was a significantly higher level of cellular GSH when grown in de Man Rogosa and Sharpe (MRS) broth than in tryptone phytone yeast extract (TPY) broth or bromcresol pruple dextrose (BCP) broth (p<0.05). The antioxidant activity of cell free extract of Lactobacillus spp. have been shown to be significantly different among strains in the inhibition of linoleic acid peroxidation by thiobarbituric acid (TBA) test (p<0.01). L. casei HY 2782 and L. acidophilus ATCC 4356 revealed a high degree of antioxidative effect in linoleic acid oxidation system. Spearmans' rank correlation coefficient between inhibitory activity on linoleic acid peroxidation and cellular GSH levels of Lactobacillus spp. was 0.65, which means a significant positive correlation.

• Toxicological Research
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• v.16 no.2
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• pp.133-139
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• 2000

This study was designed to evaluate the mechanism by which reactive nitrogen intermediates (RNI) induced the cytotoxicity of human doparminergic neuroblastoma SH-SY5Y cells. 3-Morpholino-sydnonimine (SIN-l), a donor of peroxynitrite (ONOO) and sodium nitroprusside (SNP), a donor of nitric oxide (NO) induced cell detachment and apoptotic death, as characterized by chromatin condensation, the ladder pattern fragmentation of genomic DNA and morphological nuclear changes. SIN-l also induced the activation of caspase 3-like protease in a time-dependent manner. Exogenous antioxidants, such as reduced glutathione (GSH), N-acetylcysteine (NAC), and selenium protected the cells from apoptotic death and reduced the activation of caspase 3-like protease by SIN-1. Furthermore, SIN-l directly reduced the intracellular levels of glutathione. Taken together, these data suggested that RNI including NO and peroxynitrite decrease the concentration of intracellular antioxidant such as GSH, which lead to the apoptotic death of human neuroblastoma SH-SY5Y cells.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.1
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• pp.97-110
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• 2006

Purpose : To address the ability of Myrrha (MY) to induce cell death, we investigated the effect of MY on apoptosis. In human cervical carcinoma HeLa cells, apoptosis occurred following MY exposure in a dose-dependent manner. Methods : We have tested several kinds of anti-oxidants to investigate the MY-induced apoptotic mechanism. Among the anti-oxidants, N-acetyl cysteine(NAC) or reduced glutathione (GSH) protects MY-induced apoptosis. NAC is an aminothiol and synthetic precursor of intracellular cysteine and GSH. To confirm the role of GSH in MY-induced apoptosis, methionine and cystathionine-glutathione extrusion inhibitors were treated in the presence of MY. Results : NAC, GSH, methionine or cystathionine led to protective effect against MY-induced apoptosis in HeLa cells. The GSH and GSH-associated reagents regulate MY-induced cytochrome c release and the resultant caspase-3 activation. Furthermore, the two specific inhibitors of carrier-mediated GSH extrusion, methionine and cystathionine demonstrate GSH extrusion occurs via a specific mechanism. While decreasing GSH extrusion and protecting against MY-induced apoptosis, methionine and cystathionine failed to exert anti-apoptotic activity in cells previously deprived of GSH. Conclusion : the target of the protection is indeed GSH extrusion. This shows that the protective effect is achieved by forcing GSH to stay within the cells during apoptogenic treatment. All this evidence indicates the extrusion of GSH precedes andis responsible for the apoptosis, probably by altering the intracellular redox state, thus giving a rationale for the development of redox-dependent apoptosis in MY-treated human cervical carcinoma HeLa cells.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.272-275
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• 1999

Generally, it is known that the composition of the cation of the dog's RBCs is high in potassium(K) and low in sodium(Na). However, it is reported that certain kinds of dogs have HK, HG phenotype which contains a large amount of reduced glutathione(GSH) by the effect of Na-K pump on the cell membrane of RBC with high concentration of K and low concentration of Na. Although this HK phenotype is not regarded as a disease, it is supposed to be an important assignment to examine the distribution and the occurrence rate of the dogs that contain HK cell in their RBCs for the proper clinical treatments as these HK dogs are very sensitive to aromatic disul-fide or onions and have a tendency to cause hemolysis. Accordingly, present study was performed to measure the concentration of K, Na and GSH in the RBCs of Jindo dogs and that of Dosa dogs at the same time.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.61-61
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• 2003

We have cloned the CGR1 gene encoding glutathione reductase (GR) which catalyzes the reduction of oxidized glutathione (GSSG) to reduced glutathione (GSH) from Candida albicans. The cgr1/cgr1 mutants were not viable when CaMAL2 promoter repressed the CGR1 expression. The growth of the mutants could be partially overcome by thiol compounds such as GSH, dithiothreitol, cysteine, N-acetylcysteine and GSSG. Interestingly, C. albicans with CGR1 overexpressed showed defective hyphal growth on solid medium and attenuated virulence. We have also cloned the GCS1 gene encoding ${\gamma}$-glutamylcysteine synthetase which catalyzes the first step of glutathione biosynthesis. The gcs1/gcs1 mutants were nonviable in minimal defined medium. The growth of the mutants could be resumed by supplementing with GSH, GSSG and ${\gamma}$-glutamylcysteine in the medium. The mutants had increased intracellular D-erythroascorbic acid level up to 2.25-fold when transferred to GSH-free medium. When the mutants were depleted of GSH, they showed typical markers of apoptosis. In conclusion, these results suggest that glutathione is an essential metabolite, and involved in hyphal growth, virulence and apoptosis in C. albicans.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7603-7609
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• 2014

Glutathione is a thiol compound that plays an important role in the antioxidant defense system of the cell and its deficiency leads to an increased susceptibility to oxidative stress and, thus, progression of many disease states including head and neck cancer. In the present study, alterations of glutathione levels were investigated in study cohort of 500 samples (cohort 1 containing 200 head and neck cancer blood samples along with 200 healthy controls and cohort II with 50 head and neck squamous cell carcinoma tissue samples along with 50 control tissues) by high performance liquid chromatography. The results indicated that mean blood glutathione levels were significantly reduced in head and neck cancer patients (p<0.001) compared to respective controls. In contrast, the levels of glutathione total (p<0.05) and glutathione reduced (p<0.05) were significantly elevated in head and neck squamous cell carcinoma tissues compared to the adjacent cancer-free control tissues. In addition to this, pearson correlation performed to correlate different tissue glutathione levels (GSH) with clinical/pathological parameters demonstrated a significant negative correlation between pT-stage and GSH level ($r=-0.263^{**}$; p<0.01), C-stage and GSH level ($r=-0.335^{**}$; p<0.01), grade and GSH ($r=-0.329^{**}$; p<0.01) and grade versus redox index ($r=-0.213^{**}$; p<0.01) in HNSCC tissues. Our study suggests that dysregulation of glutathione levels in head and neck cancer has the potential to predict metastasis, and may serve as a prognostic marker.

• BMB Reports
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• v.44 no.3
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• pp.170-175
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• 2011

We identified a bovine $B_{12}$ trafficking chaperone bCblC in Bos taurus that showed 88% amino acid sequence identity with a human homologue. The protein bCblC was purified from E. coli by over-expression of the encoding gene. bCblC bound cyanocobalamin (CNCbl), methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl) in the base-off states and eliminated the upper axial ligands forming aquo/hydroxocobalamin ($OH_2$/OHCbl) under aerobic conditions. A transition of $OH_2$/OHCbl was induced upon binding to bCblC. Interestingly, bCblC-bound $OH_2$/OHCbl did not react with reduced glutathione (GSH), while the reaction of free$OH_2$/OHCbl with GSH resulted in the formation of glutathionylcobalamin (GSCbl) and glutathione disulfide (GSSG). Furthermore we found that bCblC eliminates the GSH ligand of GSCbl forming $OH_2$/OHCbl. The results demonstrated that bCblC is a $B_{12}$ trafficking chaperone that binds cobalamins and protects $OH_2$/OHCbl from GSH, which could be oxidized to GSSG by free $OH_2$/OHCbl.

• Environmental Analysis Health and Toxicology
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• v.11 no.3_4
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• pp.53-57
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• 1996

In this study we investigated the effect of hydroxybrazilin on glutathione depletion induced by BrCCl$_3$ and menadione in cultured hepatocytes to understand the cellular mechanisms of hepatoprotective effect of hydroxybrazilin. Hydroxybrazilin alone had no effect on total glutathione level and the ratio of reduced glutathione/total glutathione (GSH/(GSSG+GSH)). BrCCl$_3$ dramatically decreased total glutathione level and hydroxybrazilin significantly prevented glutathion depletion by BrCCl$_3$. The ratio of GSH/(GSSG+ GSH) was also decreased by BrCCl$_3$ and recovered by hydroxybrazilin treatment. Menadione decreased total glutathione level and the ratio of GSH/(GSSG+GSH) but hydroxybrazilin showed no significant effects on menadione-induced glutathione depletion. These data suggest that hydroxybrazilin might prevent the hepatotoxicity induced by chemicalderived radicals but not the toxicity linked with oxidative stress.

• YAKHAK HOEJI
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• v.47 no.6
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• pp.432-437
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• 2003

It has been known that quercetin, a bioflavonoid widely distributed in fruits and vegetables as dietary-derived flavonoid and exert significant multiple biological effects such as antioxidant and anti-inflammatory, anti-tumor effects. In addition, it has been shown to have a chemoprotective role in cancer, though complex effects on signal transduction involved in cell proliferation and angiogenesis. The present study investigated whether quercetin can enhance antioxidant enzyme activity (glutathione peroxidase: GPx, superoxide dismutase: SOD, catalase: CAT) and regulate the reactive oxygen species (ROS) generation in the presence of vitamin E, L-ascorbic acid, reduced glutathione (GSH) on B16F10 murine melanoma cells. After 48h treatment of cells with quercetin in the presence of vitamin E, L-ascorbic acid, GSH, we measured the cytotoxicities by MTT assay. The cells exhibited a dose-dependent inhibition in their proliferation in the presence of vitamin E, L-ascorbic acid, GSH respectively. We also investigated the effects of antioxidant enzyme activity and ROS generation. The antioxidant enzyme activity of quercetin in the presence of vitamin E was stronger than GSH, L-ascorbic acid, the same treatments decreased ROS generation in B16F10 murine melanoma cells. Taken together, these result demonstrate that the antioxidant effect of quercetin can enhanced in the presence of vitamin E and it might plays an important role in anti-oxidative effects.