• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.14-20
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• 2007

In order to examine the differences in antioxidant enzyme activities which represent defence mechanism to stressful environments, and soil properties between healthy and declining (or unhealthy) trees, we selected three sites, Witseorum, Youngsil and Sungpanak (Jindallebat). Antioxidant enzymes including Ascorbate peroxidase (APX) and Glutathione Reductase (GR), forest soil properties including soil texture, soil pH, organic matter, total nitrogen, available phosphate, cation exchange capacity, exchangeable cation content and nutrient contents in leaves of Abies koreana (Korean fir) trees were analyzed. There were no significant differences between healthy and declining trees in GR activity. However, seasonal difference in antioxidant enzyme activity was observed. GR activity was lower in June and August than that of September. Soil chemical and physical properties of each site showed a tendency that organic content, total nitrogen content, available phosphorus, cation exchange capacity and cation content were lower at the site of declining trees than the site of healthy trees.

• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.267-271
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• 1998

Cotyledon explants of lettuce were cocultured with Agrobacterium tumefaciens LBA4404::pBKS-GR1 harboring glutathione reductase(GR) gene in MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip for 48 hr. These explants were transferred to MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip, 50 mg/L kanamycin, and 500 mg/L carbenicillin. After 4 weeks of subculture, kanamycin-resistant shoots were obtained on selection medium. Leaves of putative transformants survived on selection medium containing 100 mg/L kanamycin. Incoporation of the GR gene into lettuce was confirmed by PCR analysis of genomic DNA. Southern blot analysis showed that ECL-labeled GR gene was hybridized to the expected amplified genomic DNA fragment of about 1.8 kb from transgenic lettuce. The presence of mRNA in transgenic lettuce was confirmed by RT-PCR with total RNA of transgenic lettuce. In progeny test of transformants, R$_1$ seeds were resistant to kanamycin (200mg/L) on MS medium.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.95-101
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• 2009

In this study, we assessed the effects of Se-methylselenocysteine (MSC) pretreatment on the antioxidant system in the pancreas and the development of alloxan-induced diabetes in rats. The rats were treated with MSC at a dose of 0.75 mg/rat/day for 2 weeks. The MSC-treated rats evidenced significantly increased glutathione content, GSH/GSSG ratio, and glutathione peroxidase (GPx) and glutathione reductase (GRd) activities in the pancreas. Diabetes was induced via alloxan injection. The alloxan-diabetic rats evidenced significantly reduced glutathione content and glucose 6-phosphate dehydrogenase (G6PD) activity and increased catalase activity in the pancreas, when measured 3 days after the alloxan injection. 2-week MSC pretreatment was shown to prevent the alloxan-induced hyperglycemia as well as changes in glutathione content, G6PD activity, and catalase activity. The results of this study indicate that the prevention of alloxan-diabetes by MSC pretreatment is associated with its effects on antioxidants in the pancreas, namely, the increase in cellular content and the reduction of glutathione by the facilitation of glutathione recycling induced via increased GPx, GRd, and G6PD activities.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.11-20
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• 2001

Cancer chemoprevention refer to the use of natural or synthetic substances to prevent the initiational and promtional events that occur during the process of carcinogenesis. The effect of Prunella Herba Vulgaris L. Aqua-acupuncture Solution (PVAS) and Prunella Herba Vulgaris L. Water-extracted Solution (PVWS) on the induction of phase II detoxification enzyme (quinone reductase, Glutathione S-transferase) and inhibition of phase I enzyme (cytochrome P4501A1) and benzo[a]pyrene-DNA adduct formation was examined. PVAS is potent inducers of quinone reductase activity. Glutathione levels were increased with PVAS, in cultured murine hepatoma Hepa1c1c7 cells. In addition glutathione S-transferase levels were increased with PVAS. However, there was 45.2% inhibition in the activity of cytochrome P4501A1 enzyme with the treatment of PVAS, $5{\times}$. At concentration of $1{\times}$ and $3{\times}$ of PVAS, the binding of $[^3H]B[a]P$ metabolites to DNA of NCTC-clone 1469 cell was inhibited by 25.3%, 45.0%, respectively. These results suggest that PVAS has chemopreventive potential by inducing quinone reductase and glutathione S-transferase activities, increasing GSH levels, inhibiting the activity of cytochrome P4501A1 and benzo[a]pyrene-DNA adduct formation.

• Biomedical Science Letters
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• v.20 no.2
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• pp.56-61
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• 2014

This study attempted to confirm the antioxidative potential of luteolin against tert-butyl hydroperoxide (t-BHP) induced oxidative damage and to investigate its molecular mechanism related to glutathione (GSH)-dependent enzymes in HepG2 cells. Treatment with luteolin resulted in attenuation of t-BHP induced generation of reactive oxygen species (ROS) and oxidative stress-mediated cell death. In addition, accelerated expression of GSH-dependent antioxidative enzymes, glutathione peroxidase (GPx) and glutathione reductase (GR), and heme oxygenase (HO)-1, as well as strengthened GSH content was induced by treatment with luteolin, which was in accordance with increased nuclear translocation of nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), a transcription factor for phase 2 enzymes, in a dose-dependent manner. These results suggest that the cytoprotective potential of luteolin against oxidative damage can be attributed to fortified GSH-mediated antioxidative pathway and HO-1 expression through regulation of Nrf2 in HepG2 cells.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.113-120
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• 2022

Despite concerns about the significant toxicity of copper pyrithione (CuPT) at environmental concentrations, effects of CuPT on benthic organisms have received little attention. Here, we analyzed the detrimental effects of CuPT at sublethal concentrations (1/50, 1/20, and 1/10 of the 96 h-LC50 value) for 14 days in the marine polychaete Perinereis aibuhitensis. Reduced burrowing activity and significantly decreased the acetylcholinesterase activity in response to relatively high concentrations of CuPT were identified as CuPT-triggered cholinergic inhibition. The lipid peroxidation marker, malondialdehyde levels were dose-dependently increased, whereas intracellular glutathione was depleted by relatively high concentrations. In the CuPT-treated polychaete, significant fluctuations in the enzymatic activities of the antioxidant defense system (catalase, superoxide dismutase, glutathione reductase, and glutathione peroxidase) were observed with significantly modulated glutathione 𝘚-transferase activity. These results indicate that even sublethal levels of CuPT would have detrimental effects on the health status of the marine polychaete.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.258-266
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• 2020

Background: Oxidative stress-induced cardiomyocytes apoptosis is a key pathological process in ischemic heart disease. Glutathione reductase (GR) reduces glutathione disulfide to glutathione (GSH) to alleviate oxidative stress. Ginsenoside Rb1 (GRb1) prevents the apoptosis of cardiomyocytes; however, the role of GR in this process is unclear. Therefore, the effects of GRb1 on GR were investigated in this study. Methods: The antiapoptotic effects of GRb1 were evaluated in H9C2 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, annexin V/propidium iodide staining, and Western blotting. The antioxidative effects were measured by a reactive oxygen species assay, and GSH levels and GR activity were examined in the presence and absence of the GR inhibitor 1,3-bis-(2-chloroethyl)-1-nitrosourea. Molecular docking and molecular dynamics simulations were used to investigate the binding of GRb1 to GR. The direct influence of GRb1 on GR was confirmed by recombinant human GR protein. Results: GRb1 pretreatment caused dose-dependent inhibition of tert-butyl hydroperoxide-induced cell apoptosis, at a level comparable to that of the positive control N-acetyl-L-cysteine. The binding energy between GRb1 and GR was positive (-6.426 kcal/mol), and the binding was stable. GRb1 significantl reduced reactive oxygen species production and increased GSH level and GR activity without altering GR protein expression in H9C2 cells. Moreover, GRb1 enhanced the recombinant human GR protein activity in vitro, with a half-maximal effective concentration of ≈2.317 μM. Conversely, 1,3-bis-(2-chloroethyl)-1-nitrosourea co-treatment significantly abolished the GRb1's apoptotic and antioxidative effects of GRb1 in H9C2 cells. Conclusion: GRb1 is a potential natural GR agonist that protects against oxidative stress-induced apoptosis of H9C2 cells.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.355-361
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• 1997

This study was carried out to investigate the acute cutaneous enzymatic antioxidant activity of green tea extracts (GTE) on hairless mice skin after a signal exposure to ultraviolet B radiation. GTE has been in corporated at concentration of 5, 25, 50 and $100\;{\mu}g$ into hairless mice skin. Under exposure conditions of $1.0\;joule/cm^{2}$, impairment of cutaneous enzymatic activity was observed. Catalase and glutathione reductase were significantly influenced in dose-dependent manner by GTE, however glutathione peroxidase and superoxide dismutase were not affected. To measure inhibition effect of the GTE on lipoxygenase. $50\;{\mu}g$ GTE extract was added in vitro to arachidonis acid. GTE showed higher inhibition effect on 5-hydroxyeicosatetraenoic acid (HETE) and 8-HETE than metalolic products of 12- or 15-HETE. The addition of 5, 25, 50 and $100\;{\mu}g$ GTE inhibited the metabolite formation of 5-HETE by 32, 52, 62 and 80%, respectively, and the metabolite formation of 8-HETE by 36, 47, 70 and 84%, respectively.

• Journal of Life Science
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• v.9 no.6
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• pp.684-691
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• 1999

Gamdutang aqua-acupuncture solution (GAS), Gamdutang water-extracted solution (GWS) and Dae-Gamdutang aqua-acupuncture solution (DGAS) were prepared and tested for chemopreventive potentials. GAS was potent inducer of quinone reductase (QR) activity in Heapa1c1c7 murine hepatoma cells in culture, whereas GWS is less potent. GAS, GWS and DGAS were significantly induced QR activity in cultured rat normal liver cell, Ac2F. Glutathione (GSH) levels were increased about 1.8, 1.0 and 1.1 fold with GAS, GWS and DGAS in Hepa1c1c7 cells, respectively. In addition glutathione S-transferase (GST) activity was increased with GAS, GWS and DGAS. The effects of GAS, GWS and DGAS on the growth of Acanthamoeba castellanii were tested. Proliferation of A. castellanii was inhibited by GAS, GWS and DGAS at concentrations of 1 $\times$ and 5$\times$. These results suggest that GAS has chemopreventive potential by inducing QR and GST activities, increasing GSH levels and inhibition of polyamine metabolism.

• YAKHAK HOEJI
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• v.44 no.3
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• pp.283-292
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• 2000

Angelicae gigantis Radix aqua-acupuncture solution (AGRAS) and Angelicae gigantis Radix water-extracted solution (AGRWS) were prepared and tested for their organ toxicities and chemopreventive potentials. The organ-toxicity of AGRAS to male ICR mice was studied by the measurements of glutamic oxaloacetic transaminase (GOT), glutamic pyruvate transaminase (GPT), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP-s) activities after injection of AGRAS for 7 days. The activities of GOT GPT and LDH were decreased, but the activity of ALP-s was not changed with AGRAS. When AGRAS was administered once daily for 10 days before the tumor implantation, AGRAS exerted antitumor activity by inhibiting the growth of Ehrich ascites tumor cells (EATC) in viva. The inductions of quinone reductase (QR), glutathione (GSH) and glutathione S-transferase (GST) and inhibition of polyamine metabolism were tested for the chemopreventive potentials of AGRAS and AGRWS. AGRAS was potent inducer of QR activity in murine hepatoma Hepalclc7 cells. In cultured rat Ac2F cells, AGRAS was also significantly induced QR activity GSH levels were increased about 1.3 fold with AGRAS. In addition the activity of GST was increased about 2.5 fold with AGRAS at the concentration of $0.1{\;}{\times}{\;}$. The effects of AGRAS and AGRWS were tested on the growth of Acanthamoeba castellanii. Proliferation of Acanthamoeba castellanii in a broth medium was inhibited by AGRAS and AGRWS at the concentration of $1{\;}{\times}{\;}and{\;}5{\;}{\times}{\;}$, respectively: These results suggest that AGRAS has chemopreventive potential by inducing QR activity increasing GSH and GST levels and inhibition of polyamine metabolism.