• BMB Reports
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• v.35 no.3
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• pp.297-301
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• 2002

Membrane lipid peroxidation processes yield products that may react with DNA and proteins to cause oxidative modifications. The oxyR gene product regulates the expression of enzymes and proteins that are needed for cellular protection against oxidative stress. Upon exposure to tert-butylhydroperoxide (t-BOOH) and 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH), which induce lipid peroxidation in membranes, the Escherichia coli oxyR overexpression mutant was much more resistant to lipid peroxidation-mediated cellular damage, when compared to the oxyR deletion mutant in regard to growth kinetics, viability, and DNA damage. The deletion of the oxyR gene in E. coli also resulted in increased susceptibility of superoxide dismutase to lipid peroxidation-mediated inactivation. The results indicate that the peroxidation of lipid is probably one of the important intermediary events in free radical-induced cellular damage. Also, the oxyR regulon plays an important protective role in lipid peroxidation-mediated cellular damage.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.285-292
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• 2008

Crocin is one of the major components of gardenia fruit and saffron which are widely used as natural food colorants and as traditional Chinese medicines. However, the genotoxicity data on crocin are not sufficient for safety evaluation. The purpose of this study was the examination of the genotoxicity on crocin from gardenia yellow in bacterial and mammalian cells, using various genotoxic battery testing assays and the influence of crocin on methyl methanesulfonate (MMS) and ${H_2}{O_2}$-induced DNA damage in vitro, using single cell gel electrophoresis (comet) assay. From results, no considerable mutagenicity and clastogenicity were seen in bacteria and mammalian cells treated with crocin, by Ames test, chromosomal aberration assay, ${tk}^{+/-}$ gene forward mutation assay and comet assay. And, post-treatment with crocin significantly suppressed ${H_2}{O_2}$-induced DNA damage in a dose-dependent manner. In conclusion, the findings of the present study and other previous observations indicate that crocin has no genotoxic potential. And it showed that crocin clearly repressed the genotoxic potency of ${H_2}{O_2}$. These results suggest that anti-oxidative effects of crocin may be involved in the protective effects of DNA damage.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.36-39
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• 2003

Many defined cell culture media were formulated over 3() years ago and may be deficient in certain micronutrients whose essentiality has only subsequently been recognised. The objective of this study was to evaluate whether alpha-minimal essential medium (MEM) supplemented with 10% foetal bovine serum contained sufficient selenium for optimal activity of the selenium containing enzymes cytosolic glutathione peroxidase (cGPx) and phospholipid hydroperoxide glutathione peroxidase (PHGPx) in cultured Chinese hamster ovary (CHO) cells. Additionally, the effect of zinc deficiency and metallothionein (MT) overexpression on cGPx and PHGPx activity was studied. The addition of 100 nM of selenous acid to the culture medium increased cGPx expression by 10-fold and PHGPx by about 2-fold in both wild-type CHO-K1 cells and CHO-K1 cells overexpressing mouse MT-1. Zinc deficiency had no significant effect on enzyme activity, but cells overexpressing mouse MT-1 had higher levels of cGPx activity. Zinc deficiency decreased cell survival but overexpression of MT-1 was partially protective, probably because its presence in quantity favoured the uptake, sequestration and cellular retention of any remaining zinc. This study demonstrates that selenium in complete alpha-MEM is insufficient for optimal cGPx and PHGPx activity and may compromise the cellular response to oxidative stress.

• The Korean Journal of Community Living Science
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• v.13 no.2
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• pp.1-11
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• 2002

This study was conducted to estimate the amounts of the electromagnetic wave penetrating from a cellular phone in a pocket of dress shirt, as well as to test how different the penetration amounts were under the conditions of wearing. It was also investigated the possibilities that the amounts of the electromagnetic wave penetrating could be decreased by using twofold pocket or electromagnetic wave free fabric. The amounts of the electromagnetic wave penetrating were measured in the following five cases; one-layered pocket with 10 different fabrics as dress shirt, a pocket adding a layer of knitted cotton, two-layered pocket with same fabric as dress shirt, two-layered pocket adding a layer of knitted cotton, and one-layered pocket adding a layer of electromagnetic wave free fabric. Each of these five cases were measured using the front and back sides of a cellular phone facing to the body. The results were as follows; 1) The amounts of the electromagnetic wave penetrating were not significantly different in 10 different fabrics and were all above the caution range (0.02mW/$cm^2$). 2) The amounts of the electromagnetic wave penetrating in cases of the back side of the cellular phone to the body, were more than in cases of the front side. 3) There is a significantly differences in part on adding a knitted under wear to one and two layers of the pocket in the case of penetration amount under the wearing conditions. 4) The amounts of the electromagnetic wave penetrating in cases of adding a layer of electromagnetic wave free fabric, were close to the safe standard value of it. The above results suggested that facing the front side of cellular phone to the body and using extra layering with some electromagnetic wave free fabrics might have some protective effects again to the penetration amounts.

• Journal of Ginseng Research
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• v.27 no.2
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• pp.52-55
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• 2003

The present experiment was perf'3rmed to investigate the protective effects of ginseng total saponin (GTS) and possible mechanisms on the hepatocytotoxicity induced by tert-butylhydroperoxide (t-BuOOH), 4-Bromo-calciumu ionophore A23187 (Br-A23187) and KCN. Hepatocytes were isolated by collagenase perfusion of livers from fasted male Sprague Dawley rats and cultured overnight. After various treatments in Krebs-Ringer-HEPES buffer at pH 7.4, cell viability was determined by propidium iodide using fluorocytometry. GTS (5-20 ${\mu}$M) inhibited cell killing induced by t-BuOOH, and KCN, dose-dependently. However, GTS did not inhibit Br-A23187-induced cell killing. These findings support that GTS could protect the hepatocytoxicity induced by some toxic chemicals. The mechanisms of these protective effects by GTS seem to be associated with antioxidant activity and increase of cellular ATP.

• Natural Product Sciences
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• v.13 no.2
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• pp.101-104
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• 2007

Four isoflavones including tectorigenin (1), irisflorentin (2), irigenin (3), and tectoridin (4) have been isolated from the 70% EtOH extract of Belamcanda chinensis rhizome. The evaluation for protective effect of compounds 1-4 against glutamate-induced cytotoxicity in hippocampal HT22 cell line was conducted. Compound 1 showed significant protective effect with an EC$_{50}$ value of 67.25 ${\pm}$ 1.2 ${\mu}$M, whereas compounds 2-4 were inactive. These results suggest that compound 1 may possess the neuroprotective activity against oxidative cellular injures.

• Journal of Microbiology
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• v.43 no.5
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• pp.437-442
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• 2005

Sera from rabbits were infected with Vibrio vulnificus containing an antibody against major outer membrane protein (MOMP). MOMP of V. vulnificus ATCC 27562 were isolated and purified by Sarkosyl and TritonX-100 dual treatment. Molecular size of MOMP was identified as 36-kDa on $13\%$ SDS-PAGE. The sequence of the first 26 amino acid residues from the N-terminal end of the protein is AELYNQDGTSLDMGGRAEARLSMKDG, which is a perfect match with OmpU of V. vulnificus CMCP6 and YJ016. MOMP specific IgM and IgG were investigated in groups of mice. The group of mice immunized with MOMP and Alum showed higher levels of IgG2b than the group immunized with only MOMP. Vaccination with MOMP resulted in protective antibodies in the mouse infection experiment.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.298.1-298.1
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• 2003

The aim of this study was to investigate the protective effect of acanthoic acid on liver injury induced by either tertiary-butyl hydroperoxide (tBH) or carbon tetrachloride in vitro and in vivo. Acanthoic acid, (-)-pimara-9(11),15-diene-19-oic acid, is a diterpene isolated from the root bark of Acanthopanax koreanum. In in vitro study, the cellular leakage of lactate dehydrogenase (LDH) with 1.5 mM tBH for 1 j, were significantly inhibited by treatment with acanthoic acid(25 and 5mg/mL). (omitted)

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.174-187
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• 2002

Objectives : This study was carried out to determine whether Kamihaengche-tang plus Yulanijihwang-tang (KCYH) exerts a protective effect against oxidant-induced liver cell injury. Methods : Cell injury was estimated by measuring lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) release, and lipid peroxidation was estimated by measuring malondialdehyde, a product of lipid peroxidation in rabbit liver slices. Results : Oxidants (tBHP and $H_2O_2$) increased dose-dependently LDH release which was significantly prevented by 1% KCYH. The protective effect of KCYH against oxidant-induced cell injury was dose-dependent in the range of 0.05-1 % concentrations. Similarly, KCYH inhibited oxidant-induced lipid peroxidation in a dose-dependent manner. When liver tissues were exposed to Hg (0.5 mM), ALT activity in the medium and lipid peroxidation in tissues were markedly increased. These changes were prevented by 1% KCYH, KCYH restored toxicant-induced inhibition of cellular GSH content. KCYH increased the activities of catalase and glutathion peroxidase in oxidant-treated tissues. Conclusions : These results indicate that KCYH exerts a protective effect against oxidant-induced liver cell injury, and this effect is attributed to prevention of lipid peroxidation. These effects may be due to an increase in concentration of endogenous antioxidants.

• Korean Journal of Agricultural Science
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• v.39 no.1
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• pp.81-86
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• 2012

In this study, the antioxidative effect and protective potential against oxidative damage of extract and fractions from broccoli were investigated under in vitro and cellular system. The methanol (MeOH) extracts of broccoli flowers and sprouts were partitioned as dichloromethane, n-butanol (BuOH) and aqueous fractions. The comparison of antioxidative effect of broccoli flowers and sprouts showed that broccoli sprouts exerted the more effective protective activity from 2,2'-azobis (2-aminopropane) dihydrochloride (AAPH)-induced oxidative stress in LLC-$PK_1$ porcine renal epithelial cell. In addition, the extract and fractions from broccoli sprouts showed strong scavenging effect of 1,1-diphenyl-2-picrylhydrazyl radical and the BuOH fraction exerted the strongest activity. Therefore, the BuOH fraction was evaluated as the most active fraction with strong radical scavenging activity among the fractions of broccoli flowers and sprouts. The present study suggests the antioxidative potential against free radical-induced oxidative damage of flowers and sprouts of broccoli. In addition, the BuOH fraction of broccoli is considered as the active fraction with antioxidative effect.