• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.8-11
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• 2005

Experiments were performed to investigate the effects of ethanol fraction of three different rice (Oryzasativa L. var. japonica) grain (Jakwangchalbyeo, red-pericarp glutinous rice; Hwasunchalbyeo, white-pericarp glutinous rice; Ilpumbyeo, white-pericarp non-glutinous rice) extracts on the protection of oxidative stress. Antioxidant activities of ethanol fraction of rice grain extracts were made with MTT cell viability assay in H4IIE cell that is challenged with hydrogen peroxide. Hwasunchalbyeo extract and Ilpumbyeo extract did not show any significant protective effects on the $H_2O_2-induced$ oxidative stress in B4IIE cells, and Jakwangchalbyeo extract improved the cell viability up to $82\%\;and\;74\%$ at concentration of $100{\mu}g/mL$ for 5 h and 24 h treatment, respectively. In conclusion, red-pericarp Jakwangchalbyeo extract as compared with other rice extracts exerted significant inhibitory effects on the hydyogen peroxideinduced oxidative stress in the H4IIE cells.

• Journal of Medicine and Life Science
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• v.17 no.2
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• pp.41-46
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• 2020

Metformin, a predominantly prescribed anti-diabetic drug for decades, has gained new insights for its anti-tumor activity in a variety of cancer cells. Our previous studies also showed the obvious pro-apoptotic activity of metformin and the underlying action mechanisms in hepatocellular carcinoma cells. Together with apoptosis, autophagy is a crucial intracellular process to determine the survival or death of cells under some stressful environments. The present study aimed to determine the role of autophagy in metformin-induced death of H4IIE hepatocellular carcinoma cells. Metformin blocked the formation of autophagosome and the expression of LC3A, generally described as a biomarker of autophagy. Inhibition of AMPK reversed the metformin-induced blockade of autophagy. Antioxidant (NAC) suppressed the metformin-induced cell death but not affected LC3A. The inhibition of protein kinase C totally restored the metformin-suppressed expression of LC3A. In summary, our present study suggests that autophagy is an anti-apoptotic player in metformin-induced apoptosis in H4IIE cells.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.98-98
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• 2004

• Food Science and Biotechnology
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• v.15 no.4
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• pp.534-542
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• 2006

The effects of ethanol fractions of three different rice grain extracts, Jakwangchalbyeo, Hwasunchalbyeo, and Ilpumbyeo, on apoptotic cell death in the rat hepatoma H4IIE cell line were investigated using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell viability assay. One hundred mg/mL Jakwangchalbyeo extract significantly reduced cell viability to 69.5, 57.2, and 46.1% within 24, 48, and 72 hr, respectively. Fluorescence-activated cell sorting (FACS) analyses were also performed to characterize the cell death pattern caused by treatment with the rice grain extracts. Apoptotic cell death was clearly observed with time after treatment with the Jakwangchalbyeo extract. In Western blotting analysis, degradation of the 116 kDa poly-ADP-ribose polymerase (PARP) molecule was observed with concomitant formation of an 89 kDa product 24, 48, and 72 hr after treating cells with the Jakwangchalbyeo extract. This indicates that an apoptotic process caused cell death in these cells. In conclusion, red-pericarp Jakwangchalbyeo extract induced apoptotic cell death in H4IIE cells to a larger extent than the other rice extracts.

• Development and Reproduction
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• v.27 no.2
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• pp.77-89
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• 2023

Metformin is the most widely used anti-diabetic drug that helps maintain normal blood glucose levels primarily by suppressing hepatic gluconeogenesis in type II diabetic patients. We previously found that metformin induces apoptotic death in H4IIE rat hepatocellular carcinoma cells. Despite its anti-diabetic roles, the effect of metformin on hepatic de novo lipogenesis (DNL) remains unclear. We investigated the effect of metformin on hepatic DNL and apoptotic cell death in H4IIE cells. Metformin treatment stimulated glucose consumption, lactate production, intracellular fat accumulation, and the expressions of lipogenic proteins. It also stimulated apoptosis but reduced autophagic responses. These metformin-induced changes were clearly reversed by compound C, an inhibitor of AMP-activated protein kinase (AMPK). Interestingly, metformin massively increased the production of reactive oxygen species (ROS), which was completely blocked by compound C. Metformin also stimulated the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK). Finally, inhibition of p38MAPK mimicked the effects of compound C, and suppressed the metformin-induced fat accumulation and apoptosis. Taken together, metformin stimulates dysregulated glucose metabolism, intracellular fat accumulation, and apoptosis. Our findings suggest that metformin induces excessive glucose-induced DNL, oxidative stress by ROS generation, activation of AMPK and p38MAPK, suppression of autophagy, and ultimately apoptosis.

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.105-109
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• 2000

The purpose of this study is to investigate on the water quality of the upper region of Wonchun stream located in Suwon city by chemical analysis and EROD-microbioassay methods using rat hepatoma cell line H4IIE. The water samples were collected at 6 sampling sites from sept. to Nov. 1999 and determined the quantitative toxic effects. Higher levels of BO $D_{5}$, CO $D_{Cr}$ and CO $D_{Mn}$ were determined at M6 site where the influent contains domestic and industrial wastewater. EROD activity of water samples was ranged from 3.43$\pm$0.08 to 9.05$\pm$0.10 pmol/mg protein/min. High correlation with EROD activities and COD values was observed. From the results, the upper region of Wonchun stream water area was presumed to be highly polluted with various persistent organic chemicals.s.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.349-360
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• 2011

The objectives of present study were to characterize the peptides which were isolated from Korean fermented soybean paste, chungkukjang, and to determine their antioxidant activities. Four fractions were collected from the methanol extract of chungkukjang by using a recycling preparative HPLC. Among fractions, Fr-2 was identified to be highly potent free radical scavenging activity in the assay of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and nitroblue tetrazolium(NBT)-reduction inhibition. Base on antioxidant effects, fraction Fr-2 was employed for the refraction with a prep-column and separated into five fractions of which two fractions were identified to have higher antioxidant activity. To confirm the amino acid constituents of antioxidant fractions Fr-2-2 and Fr-2-3 were analyzed, and eight kinds of amino acids such as aspartic acid, threonine, serine, glutamic acid, glycine, lysine, histidine, and arginine were identified as the constituent amino acids. Antioxidant activities of the separated peptides were further assessed cell viability with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl terazolium bromide (MTT), and fluorescence-activated cell sorting (FACS) analysis of H4IIE cells treated with hydrogen peroxide (H2O2). Chungkukjang peptides have shown their ability to protect H4IIE rat hepatoma cells against H2O2- induced oxidative stress by concentration and time-dependent manner. Therefore, These results indicated that fermented soybean paste chungkukjang will be promoted the antioxidant and radical scavenging activities, and beneficial for health. The antioxidant peptide fractions Fr-2-2 and Fr-2-3 were denominated as P-NICS-1 and P-NICS-2, respectively. However, further studies were required to clarify their amino acid sequences and molecular properties, and physiological significances.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.249-257
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• 2010

Crataegii Fructus is commonly used as a improving digestion, removing retention of food, promoting blood circulation and resolving blood stasis agent in East Asia. Cadmium (Cd) is widely distributed in the environment due to its use in industry. An exposure to Cd causes dysuria, polyuria, chest pain, hepatic and renal tubular diseases. The liver is the most important target organ when considering Cd-induced toxicity because Cd primarily accumulates in the liver. This study investigated the protective effect of Crataegii Fructus water extract against cadmium ($CdCl_2$, Cd)-induced liver toxicity in H4IIE cells, a rat hepatocyte-derived cell line and in rats. Cell viability was significantly reduced in Cd-treated H4IIE cells in a time and concentration-dependent manner. However, Crataegii Fructus water extract (CFE) protected the cells from Cd-induced cytotoxicity via inhibition of PARP cleavage. To induce acute toxicity in rats, Cd (4 mg/kg body weight) was dissolved in normal saline and intravenously injected into rats. The rats then received either a vehicle or silymarin (as a positive control) or CFE (50, 100 mg/kg/day) for 3 days, and were subsequently exposed to a single injection of Cd. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were significantly increased by Cd treatment. In contrast, pretreatment with CFE reduced ALT, AST and LDH. In histopathological analysis, CFE reduced the hepatic degenerative regions and the number of degenerative hepatocytes. These are considered as direct evidences that Crataegii Fructus has favorable inhibitory effects on the Cd-intoxicated liver damages. The efficacy of Crataegii Fructus shows slight lower than that of silymarin in the present study.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.72-72
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• 2003

Induction of glutathione S-transferases is associated with cancer chemoprevention. We reported that PD98059, an MKK1 inhibitor, induces glutathione Stransferase A2 (rGSTA2). This report comparatively examines the role of CCAAT/enhancer binding protein (C/EBP) and Nrf-2 in the induction of rGSTA2 by PD98059. PD98059 at the concentrations effective for the inhibition of MKKI increased the rGSTA2 protein and mRNA levels in H4IIE cells. (omitted)