• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1390-1393
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• 2007

In this study, three of the representative EDCs, $17{\beta}$-estradiol, bisphenol A, and styrene, were employed to find their mode of toxic actions in E. coli. To accomplish this, four different stress response genes, recA, katG, fabA, and grpE genes, were used as a representative for DNA, oxidative, membrane, or protein damage, respectively. The expression levels of these four genes were quantified using a real-time RT-PCR after challenge with three different EDCs individually. Bisphenol A and styrene caused high-level expression of recA and katG genes, respectively, whereas $17{\beta}$-estradiol made no significant changes in expression of any of those genes. These results lead to the classification of the mode of toxic actions of EDCs on E. coli.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.214-218
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• 2007

The water extracts of Samultang (Samul) has been used for treatment of ischemic heart and brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extract of Samul rescues cells from oxidative damages in cisplatin-induced ototoxicity. Cisplatin is a widely used chemotherapeutic agent that is also highly ototoxic. This study was designed to investigate the protective effects of Samul on ciplatin-induced ototoxicity in HEI-OC1 auditory cells and organ of Corti explant culture. Cisplatin markedly decreased the viability of HEI-OC1 auditory cells. However, treatment of HEI-OC1 cells with Samul significantly reduced cisplatin-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Cisplatin induced cytotoxicity in isolated and cultured hair cell progenitors from postnatal rat cochleae. These progenitor cells are isolated from the lesser epithelial ridge (LER, or outer spiral sulcus cell) area of pre-plated neonatal rat cochlear segments. However, Samul completely protected the morphological changes of organ of Corti and LER. Taken together, these data suggest that the protective effects of the water extracts of Samul against cisplatin may be mediated by the reduction of intracellular peroxide generation.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.282-286
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• 2013

Many manufacturing processes damage the structure of meat products and this often contributes to lipid oxidation which could influence warmed-over flavor (WOF) in precooked beef that is reheated beef. Electrical stimulation causes contraction of muscles and improves tissue tenderization. The purpose of this study was to evaluate the rate of lipid oxidation or warmed-over flavor that could be affected by electrical stimulation of precooked roast beef after refrigerated storage and reheating. The results show that there was no significant difference between chemical compositions and cooking yields when comparing non-electrically stimulated and electrically stimulated roast beef. Moreover, electrical stimulation had no significant effect on oxidative stability and off-flavor problems of precooked roast beef as evaluated by thiobarbituric acid reactive substances (TBARS) and sensory test (warmed-over aroma and warmed-over flavor). However, there was an increased undesirable WOF and a decrease in tenderness for both ES and Non-ES treatments over refrigerated storage time. Electrical stimulation did cause reactions of amino acids or other compounds to decrease the desirable beef flavor in re-cooked meat.

• Molecules and Cells
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• v.40 no.4
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• pp.307-313
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• 2017

Caloric restriction (CR) has been shown to extend lifespan and prevent cellular senescence in various species ranging from yeast to humans. Many effects of CR may contribute to extend lifespan. Specifically, CR prevents oxidative damage from reactive oxygen species (ROS) by enhancing mitochondrial function. In this study, we characterized 33 single electron transport chain (ETC) gene-deletion strains to identify CR-induced chronological lifespan (CLS) extension mechanisms. Interestingly, defects in 17 of these 33 ETC gene-deleted strains showed loss of both respiratory function and CR-induced CLS extension. On the contrary, the other 16 respiration-capable mutants showed increased CLS upon CR along with increased mitochondrial membrane potential (MMP) and intracellular adenosine triphosphate (ATP) levels, with decreased mitochondrial superoxide generation. We measured the same parameters in the 17 non-respiratory mutants upon CR. CR simultaneously increased MMP and mitochondrial superoxide generation without altering intracellular ATP levels. In conclusion, respiration is essential for CLS extension by CR and is important for balancing MMP, ROS, and ATP levels.

• Molecular & Cellular Toxicology
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• v.3 no.4
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• pp.299-305
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• 2007

The endocrine disrupting chemical, di (2-ethylhexyl) phthalate (DEHP) is a plasticizer used in polyvinyl chloride products ubiquitous in our daily lives. DEHP has potentially adverse effects on the liver, kidney, lung, heart, reproductive organs and endocrine systems. Many toxicological data on the DEHP toxicity have been stated, but complete protein profiles have not yet been reported. In this study, DEHP-induced oxidative DNA damage in rat lymphocyte was evaluated by Comet assay (single-cell gel electrophoresis) for the first time. Moreover, DEHP-induced protein profile alterations were examined in rat liver by using toxicoproteomic tools. 34 protein spots in the liver were identified to be significantly deregulated by DEHP on the 2-dimensional gel. Among them, 20 spots were up-regulated and 14 spots down-regulated by DEHP.

• CELLMED
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• v.4 no.1
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• pp.7.1-7.8
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• 2014

Metabolic effects of ten daily doses of standardized extract of Andrographis paniculata leaves (AP) rich in andrographolide were evaluated in a rat model of type-2 diabetes and in diet induced obese rats. AP was administered per-orally as suspension in 0.3% carboxymethylcellulose at doses of 50, 100 and 200 mg/kg/day for 10 consecutive days. Blood glucose, insulin and lipid profile of rats were measured by using enzyme kits. In addition, effects of such treatments on anti-oxidant enzymes activity and histopathological changes in various organs of diabetic rats were assessed. AP treatments reversed body weight losses and increased plasma insulin level in diabetic rats. The anti-oxidant enzymes activity became normal and histopathological changes observed in pancreas, liver, kidney and spleen of diabetic animals were less severe in extract treated groups. On the other hand, hyperinsulinemia and increased body weight gains observed in high fat or fructose fed rats were less severe in the extract treated groups. These observations revealed therapeutic potentials of the extract for treatments of diabesity associated metabolic disorders, and suggest that the effects of the extract on insulin homeostasis depend on the metabolic status of animals. Activation of cytoprotective mechanisms could be involved in its mode of action.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.293-297
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• 2003

Glutathione and ascorbic acid have been shown to fulfill many essential functions in animal and plant growth, development, defence and protection against oxidative damage. Effects of glutathione and ascorbic acid were examined in transgenic N. tabacum cells producing hGM-CSF to determine the effects of the vitamins on growth and cell viability. In lag phase, cell viability was preserved by glutathione and ascorbic acid. Therefore, recombinant protein productivity was increased. The purpose of present study is to investigate the role of antioxidants in cold stress-induced apoptosis in plant suspension cells. Cold stress lowered cell viability and increased total genomic DNA fragmentation. Supplementing the cell cultures with glutathione and ascorbic acid inhibited cold stress-induced decrease in cell viability and increase in total genomic DNA fragmentation.

• Preventive Nutrition and Food Science
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• v.17 no.4
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• pp.261-268
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• 2012

Ribes diacanthum Pall (RDP) is a member of the Saxifragaceae family. The plant is traditionally used in Mongolia for the treatment of various ailments associated with kidney and bladder's diseases, cystitis, kidney stone, and edema. This study was aimed to investigate antioxidant activities of different solvent extracts of whole Pall plants, based on ferric-reducing antioxidant potential (FRAP), 2,2'-azinobis(3-ethybenzothiazoline-6-sulfonic acid) ($ABTS{\cdot}+$) radical scavenging activity, 1,1-diphenyl-2-picrydrazyl ($DPPH{\cdot}$), and hydroxyl (${\cdot}OH$) radical scavenging activities. Additionally, total flavonoids and phenolic contents (TPC) were also determined. The ethyl acetate extract of RDP (EARDP) had a remarkable radical scavenging capacity with an $IC_{50}$ value of 0.1482 mg/mL. In addition, EARDP was shown to be higher in total phenolic and flavonoid contents than the methanol extract of RDP (MRDP). Moreover, the EARDP had the predominant antioxidant capacity, DPPH, hydroxyl, and ABTS radical scavenging activities and ferric reducing power. These results suggest a potential for R. diacanthum Pall extract as a functional medicinal material against free-radical-associated oxidative damage.

• Toxicological Research
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• v.34 no.1
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• pp.31-39
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• 2018

The objective of this study was to evaluate the antioxidant and anti-aging effects of marigold methanol extract (MGME) in human dermal fibroblasts. Total polyphenolic and flavonoid contents in MGME were 74.8 mg TAE (tannic acid equivalent)/g and 85.6 mg RE (rutin equivalent)/g, respectively. MGME ($500{\mu}g/mL$) increased 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2'-azino-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical-scavenging, and superoxide dismutase (SOD)-like antioxidant activities by 36.5, 54.7, and 14.8%, respectively, compared with the control. At $1,000{\mu}g/mL$, these activities increased by 63.7, 70.6, and 20.6%, respectively. MGME ($100{\mu}g/mL$) significantly increased the synthesis of type 1 procollagen by 83.7% compared with control treatment. It also significantly decreased Matrix Metalloproteinase-2 (MMP-2) activity and MMP-1 mRNA expression by 36.5% and 69.5%, respectively; however, it significantly increased laminin-5 mRNA expression by 181.2%. These findings suggest that MGME could protect human skin against photo-aging by attenuating oxidative damage, suppressing MMP expression and/or activity as well as by stimulating collagen synthesis.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.11-12
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• 2004

Peroxiredoxin(PRX)은 원핵세포에서 진핵세포에 이르기까지 세포 내부적으로 발생된 과산화물로부터 자신을 보호하는 중요한 항산화단백질이다. 포유류에서는 아직까지 여섯 개의 다른 동형체가 밝혀졌으며, 조류에서는 아직 발표된 바가 없다. 이 실험을 통해 최초로 조류의 PRX 단백질군들의 특성을 분석하였다. 생물정보분석기법을 통해 알아본 결과, 조류에서는 최소한 진화적으로 보존된 4개의 다른 PRX 단백질로 구성됨을 알 수 있다. 또한 닭의 PRXs로 in vitro 실험을 진행한 결과, 포유류의 것과 비슷한 항산화 활성을 나타냄을 알 수 있었다. 닭의 PRX는 조직 비특이적으로 발현하였으며, 이는 항산화 물질의 피해로부터 모든 조직을 보호하기 위한 필수적 요소이기 때문일 것으로 추정된다. 결론적으로, 생물정보분석기법을 통하여 추정할 수 있는 닭의 기능성 유전자군을 효과적으로 찾을 수 있고, in vitro 실험을 통하여 그 기능을 확인할 수 있었다.