• Korean Journal of Medicinal Crop Science
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• v.21 no.2
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• pp.136-141
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• 2013

Chelidonium majus (CM) contains several isoquinoline alkaloids that have been reported to have various biological activities such as anti-inflammatory, antimicrobial, antioxidant, immune-modulatory, and antitumoral. It has been reported that the extract of CM had an antioxidant potential, however the mechanism has not been verified. In this study, we found that CM extract activated FOXO3a. FOXO3a is a transcription factor that involved in various biological processes such as cell cycle arrest, apoptosis, DNA repair, and ROS detoxification. Transcriptional activities of FOXO3a were regulated by post-translational modifications including phosphorylation, acetylation, and ubiquitination. Protein level of FOXO3a was increased by CM extract. Promoter activities of FOXO-transcriptional target genes such as MnSOD, p27 and GADD45 were activated by CM extract in a dose dependent manner. In addition, protein level of MnSOD, major antioxidant enzyme, was increased by CM extract. Thereby ROS level was decreased by CM in old HEF cells. These results suggest that CM extract has an antioxidant activity through FOXO activation.

• Journal of Life Science
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• v.23 no.10
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• pp.1280-1287
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• 2013

The current study investigated the effects of [6]-gingerol, a ginger phytochemical, on the expression of autophagy-related genes and the activation of antioxidative enzymes in the pancreas of mice with cerulein-induced acute pancreatitis. The following were studied: pancreatic edema, ${\alpha}$-amylase activity in serum, expression of autophagy genes, activities of antioxidative defense enzymes, such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the production of lipid peroxidation (LPO). The results revealed that cerulein-induced edema in the pancreas and ${\alpha}$-amylase activity in the cerulein group significantly increased compared with that of the control. However, that of the [6]-gingerol pretreated group was significantly decreased compared with that of the cerulein-alone injected group (positive control). There was no significant difference compared with that of control. The expression of autophagy-related proteins, including Beclin-1 and cleaved microtubule-associated protein 1 light chain 3, were significantly increased in the positive control but significantly decreased in the [6]-gingerol-pretreated group. Furthermore, the activities of SOD and GSH-Px in the positive control were decreased compared with those of the control. However, those of the [6]-gingerol pretreated group were significantly increased compared with those of the cerulein-alone group. The mRNA levels and antioxidant enzyme activities were similar. The production of LPO in the cerulein with and without [6]-gingerol groups was increased by 133.1% and 26.3%, respectively, compared with that of the control, whereas that of the [6]-gingerol-pretreated group was significantly decreased by 48.5% compared with that of the positive control. Therefore, [6]-gingerol may be a strong candidate in reducing autophagy and LPO production and in enhancing antioxidative enzyme activities to help prevent acute and chronic pancreatitis.

• Toxicological Research
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• v.23 no.2
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• pp.127-133
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• 2007

Metformin is a drug used to lower blood sugar levels in patients with type 2 diabetes via activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK). The primary objective of this study was to investigate whether metformin at the pharmacologically effective concentrations affects the expressions of ${\gamma}$-glutamylcysteine synthetase and phase II antioxidant genes in the H4IIE cell. Treatment of the cells with either metformin or 5-aminoimidazole-4-carboxamide riboside (AICAR) abrogated tert-butylhydroxyquinone (t-BHQ) induction of ${\gamma}$-glutamylcysteine synthetase, a rate limiting enzyme of GSH synthesis. The ability of t-BHQ to induce glutathione S-transferases (GSTs), a major class of phase II detoxifying enzymes that playa critical role in protecting cells from oxidative stress or electrophiles, was also inhibited by the agents. Transcriptional gene repression by metformin was verified by the GSTA2 promoter luciferase assay. Moreover, either metformin or AICAR treatment significantly decreased t-BHQ-dependent induction of other GSTs (i.e., $GST{\mu}$ and $GST{\pi}$ forms). Taken together, our data indicate that metformin treatment may result in the repression of ${\gamma}$-glutamylcysteine synthetase and glutathione S-transferase genes possibly via AMPK activation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.3
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• pp.159-166
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• 2013

We have previously investigated the proteome changes of rice leaves under heat stress (Lee et al. in Proteomics 2007a, 7:3369-3383), wherein a group of antioxidant proteins and heat shock proteins (HSPs) were found to be regulated differently. The present study focuses on the biochemical changes and gene expression profiles of heat shock protein and antioxidant genes in rice leaves in response to heat stress ($42^{\circ}C$) during a wide range of exposure times. The results show that hydrogen peroxide and proline contents increased significantly, suggesting an oxidative burst and osmotic imbalance under heat stress. The mRNA levels of chaperone 60, HSP70, HSP100, chloroplastic HSP26, and mitochondrial small HSP responded rapidly and showed maximum expression after 0.5 or 2 h under heat stress. Transcript levels of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) and Cu-Zn superoxide dismutase (Cu-Zn SOD) showed a rapid and marked accumulation upon heat stress. While prolonged exposure to heat stress resulted in increased transcript levels of monodehydroascorbate reductase, peroxidase, glyoxalase 1, glutathione reductase, thioredoxin peroxidase, 2-Cysteine peroxiredoxin, and nucleoside diphosphate kinase 1, while the transcription of catalase was suppressed. Consistent with their changes in gene expression, the enzyme activities of APX and DHAR also increased significantly following exposure to heat stress. These results suggest that oxidative stress is usually caused by heat stress, and plants apply complex HSP- and antioxidant-mediated defense mechanisms to cope with heat stress.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.189-192
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• 2001

We have investigated the effects of abiotic and biotic stresses on leaf senescence using transgenic tobacco plants, in which cellular contents of polyamines were increased by introducing the genes of polyamine and ethylene biosynthesis in sense or antisense orientation. These transgenic plants showed accumulations of polyamines at higher levels than were found in wild-type. Stress-induced senescence was attenuated in transgenic plants cpmpared with wild-type plants, in terms of total chlorphyll loss and phenotypic changes after oxidative stress of hydrogen peroxide($H_2O_2$), high salinity, acid stress (pH3.0), ABA and fungal pathogen(phytophothora parasitica pv.Nicotianae). Transcripts for antioxidant enzyme, glutathionine-S-transferase and catalase, were also more abundant in transgenic plants than wild-type plants. These result suggested that higher expression of those genes caused a broad-spectrum resistance to abiotic stress/biotic stress. These phenomena indicate that polyamines may play an important role in contributing to the antioxidant defense function in plants. Our findings suggest that facilitate the improvement of stress tolerance of crop plants.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.1
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• pp.13-23
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• 2018

This study was performed to investigate the antioxidant and antidyslipidemic effects of Artemisiae iwayomogii Herba, Curcumae longae Radix and Plantaginis Semen complex extract(ACP) on HepG2 cells. We measured total polyphenols, total flavonoids, radical scavenging activity, and ABTS radical scavenging activity of ACP to evaluate its antioxidant activity. HepG2 cells were treated with ACP. Then, we evaluated ROS production; intracellular GSH content; GPx, GR, SOD, and catalase activities; free fatty acids and MDA levels; and mRNA expression levels of ACAT1 and HMG-CoA reductase. Results: ACP contains polyphenols and flavonoids and increased the DPPH and ABTS radical scavenging activities in HepG2 cells in a dose dependent manner. Also, ACP significantly reduced ROS production in HepG2 cells compared to the control group and significantly increased the GSH content, and elevated the enzyme activities of GPx, GR, and catalase in HepG2 cells compared to the control group. In addition, ACP reduced the mRNA expression of ACAT1 and HMG-CoA reductase in HepG2 cells compared to that in the control group. Conclusion: These results suggest that ACP has an antioxidant effect and may suppress the expression of dyslipidemia - associated genes and thus may be useful for the improvement of dyslipidemia.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.80-84
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• 2003

The thioredoxin peroxidase (TPx) is an antioxidant member of the peroxiredoxin family of enzymes. The TPx enzyme system has been implicated in the elimination of hydrogen peroxide and hydroxyl radicals generated during cellular processes. Such reactive molecules have been shown to cause damage to all major classes of biological macromolecules, including lipid, protein and DNA. Compared to mammalian peroxiredoxin genes, little is known about the insect TPx. (omitted)

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.642-652
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• 2018

Rhus verniciflua (RV) Stokes is a herbal medicine that helps improve blood circulation by stimulating digestion, removing extravasated blood, and raising body temperature. The purpose of this research was to study the anti-inflammatory effect of fermented soy products (FSP) containing a fermented RV (FRV) extract on lipopolysaccharides (LPS)-treatedd RAW 264.7 cells. Treatment with FRV extracts (1, 10, $100{\mu}g/mL$) downregulated nitric oxide (NO) and pro-inflammatory cytokines as compared to the LPS-treated group. Besides, the RV extract treatment suppressed the expression of genes related to pro-inflammatory cytokines, matrixins, inflammation, and apoptosis, while increasing the expression of genes involved in the antioxidant system. Furthermore, RVS extract upregulated antioxidant enzymes, such as glutathione, Cu,Zn-SOD, and catalase without changes in the Nrf2-Keap1 pathway. FSP (doenjang, ganjang) containing FRV extracts (0.1, 1, or $10{\mu}g/mL$) significantly decreased the NO and IL-6 levels in an FSP after 8 weeks of fermentation, but not the expression of genes involved in the inflammation and antioxidant system. These result indicate that an FRV extract and FSPs have a potential application in inflammatory conditions.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.914-919
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• 2006

We investigated the catechin content in green tea leaf (GTL) and green tea seed (GTS), the antiproliferative and detoxifying phase II enzyme-inducing activities of the methanolic (80%, v/v) extracts from GTL and GTS. GTL and GTS contained $8,685{\pm}1,061$ and $108{\pm}32\;{\mu}g/g$ epigallocatechin gallate (EGCG), $11,486{\pm}506$ and $116{\pm}72\;{\mu}g/g$ epigallocatechin (EGC), $3,535{\pm}308$ and $821{\pm}95\;{\mu}g/g$ epicatechin gallate (ECG), and $1,429{\pm}177$ and $37{\pm}44\;{\mu}g/g$ epicatechin (EC), respectively. The methanolic extract of GTS showed a greater increase in quinone reductase activity and antiproliferation potential against mouse hepatoma cells than GTL extract did. GTS treatment resulted in the accumulation at sub-G1 phase of mouse hepatoma hepa1c1c7 cells as assessed by flow cytometry. Enhancement of phase II enzyme activity by GTS extract was shown to be mediated, directly or indirectly, via interaction with the antioxidant response element (ARE) sequence in the genes encoding the phase enzymes. As the catechin content in GTS was significantly lower than that in GTL, components other than catechins appear to be responsible for the anticarcinogenic activity of the seed. In summary, these results suggest that the 80% methanolic extract of GTS deserves further study to evaluate its potential as an anticarcinogenic agent and to investigate its mechanism of action.

• Toxicological Research
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• v.31 no.2
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• pp.173-180
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• 2015

Extract from Gryllus bimaculatus crickets inhibits oxidation at the DNA level, with reduced production of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Microarray analyses were performed with a rat 28K cDNA clone set array to identify the gene expression profiles of aged (10 months old) Wistar Kyoto rats treated for one month with 100 mg/kg G. bimaculatus ethanol extract to assess the effects. The extract produced a meaningful anti-edema effect, evident by the inhibition of creatinine phosphokinase activity. The weights of abdominal and ovarian adipose tissues were reduced and the proportion of unsaturated fatty acids in adipose tissues was increased in an extract dose-dependent manner. Compared with untreated control rats, rats treated with the extract displayed the upregulation of 1053 genes including Fas (tumor necrosis factor receptor superfamily, member 6), Amigo3 (adhesion molecule with an immunoglobulin-like domain), Reticulon 4, 3-hydroxy-3-methylglutaryl-coenzyme (Hmgcr; a reductase), related anti-fatigue (enzyme metabolism), and Rtn antioxidant, and the downregulation of 73 genes including Ugt2b (UDP glycosyltransferase 2 family), Early growth response 1, and Glycoprotein m6a. Data suggest that G. bimaculatus extract may have value in lessening the effects of aging, resulting in a differential gene expression pattern indicative of a marked stress response and lower expression of metabolic and biosynthetic genes.