• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.290.1-290.1
• /
• 2003

Oxidative DNA damage has been associated with many disease. Quantation of DNA adducts is considered to be a useful biomarker of oxidative DNA damage because its formation can also be induced by oxidative stress. Extensive efforts have been taken to identify the analytical methods for minimizing the artifactual formation of oxidative DNA damage. We have done direct analysis of DNA adducts using LC/ESI-MS without urine sample extraction. (omitted)

• Journal of Nutrition and Health
• /
• 제33권2호
• /
• pp.167-178
• /
• 2000

The effect of oral vitamin e (800IU/day) and C (500mg/day) supplementation for 10 days and/or smoking cessation for 5 days on oxidative damage to the red blood cells (RBC) of male smokers (22.2$\pm$0.2 years old) was studied. RBC were tested for their ability to protect against smoking-induced oxidative damage by measuring heme proteins (carboxyhemoglobin, hemoglobin, methemoglobin, oxyhemoglobin), hemolysis and thiobarbiturinc acid reactive substances (TBARS). Plasma levels of vitamin c, A, E, $\beta$-catotene, total cholesterol, glutamic pyruvic transaminase(GPT) and glutamic oxaloacetic transaminase(GOT) were also analyzed. In experiment one, a comparison was made of heme proteins and lipid damage to RBC, plasma antioxidant status (indexed by plasma levels of vitamin C, E, A and $\beta$-carotene) between smokers(n=56) and non-smokers (n=16). No differences were found in plasma antioxidant status, heme protein damage and TBARS concentration of RBC. In experiment two, 46 fasting male smokers from experiment one were divided into 4 groups. The groups were smoking with placebo group(SP, n=14), smoking cessation with vitamins supplementatin group (SV, n=13), smoking cessation with placebo group (NSP, n=9) and smoking cessation with vitamins supplementation group (NSV, n=10). After supplementing antioxidant vitamins, significant increases were seen in plasma vitamins supplementation group (NSV, n=10). After supplementing antioxidant vitamins, significant increases were seen plasma vitamin C (p<0.05) and vitamin E levels (p<0.05). The plasma vitamin E level was highest in the NSV group. Vitmain E and C supplementation provided some protection against heme proteins and lipid damage by lowering methemoglobin, hemolysis and TBARS concentration of RBC. Smoking cessation significantly decreased TBARS of RBC and plasma total cholesterol concentration. Supplementing vitamin E and C with smoking cessation considerably lowered plasma total cholesterol. These results point to a special association among smoking, oxidative damage and plasma antioxidant vitamin status. They indicate that increases in plasma antioxidant status can be detected after the supplementation of vitamin C and E and that smoking cessation had an additional effect on plasma vitamin E level. The present data suggest that improved antioxidant status induced by antioxidant supplementation or smoking cessation may help prevent oxidative damage in smokers.

• 한국수산과학회지
• /
• 제50권5호
• /
• pp.520-526
• /
• 2017

Carnosine was recently reported to protect against the DNA damage induced by oxidative stress. In this study, we investigated the protective effect of eel Anguilla japonica carnosine extracts prepared using different methods (heat treatment extracts, HTEs; ion exchange chromatography, IEC; ultrafiltration permeation, UFP) on leukocyte DNA damage using the comet assay. Human leukocytes were incubated with extracts of eel carnosine at concentrations (of 10, 50, $100{\mu}g/mL$), and then subjected to an oxidative stimulus [$200{\mu}M$ hydrogen peroxide ($H_2O_2$)]. Pretreatment of the cells for 30 min with carnosine significantly reduced the genotoxicity of $H_2O_2$ measured as DNA strand breaks. The protective effects of the three types of extract (HTE, IEC, and UFP) increased with concentration. At the highest concentration (100 g/mL). there were no statistical differences in oxidative damage between each extract treatment and PBS-treated negative controls. When leukocytes were incubated with carnosine for 30 min after exposure to $H_2O_2$. the protective ability of each extract changed. Therefore, eel carnosine inhibits the $H_2O_2$ induced damage to cellular DNA in human leukocytes, supporting the protective effect of this compound against oxidative damage.

• 한국자원식물학회지
• /
• 제31권3호
• /
• pp.228-236
• /
• 2018

In this study, we evaluated the antioxidant activity and protective effects against oxidative DNA damage of the ethyl acetate fraction from the callus of Abeliophyllum distichum Nakai (ECA). Callus of A. distichum was induced on MS medium containing NAA (1 mg/L) and 2,4-D (1 mg/L), and a sufficient amount was obtained for the extraction by subculture. Acteoside was analyzed and quantified (0.39 mg/g callus) from ECA using the high-performance liquid chromatography-photodiode array detector method. ECA showed very high antioxidative activity as revealed by DPPH and ABTS scavenging assays. The $IC_{50}$ values were 12.4 and $6.8{\mu}g/ml$, respectively. ECA showed protective effects against oxidative DNA damage evaluated by using ${\Psi}X-174$ RF I plasmid DNA. It also inhibited DNA damage by suppressing the oxidative stress-induced protein and mRNA levels of ${\gamma}$-H2AX and p53 in NIH/3T3 cells. In conclusion, ECA protects against oxidative DNA damage through its powerful antioxidant activity.

• Toxicological Research
• /
• 제23권3호
• /
• pp.207-214
• /
• 2007

Chronic oxidative stress produced by exposure to environmental chemicals or pathophysiological states can lead animals to aging, carcinogenesis and degenerative diseases. Indirect antioxidative mechanisms, in which natural or synthetic agents are used to coordinately induce the expression of cellular antioxidant capacity, have been shown to protect cells and organisms from oxidative damages. Electrophile and free radical detoxifying enzymes, which were originally identified as the products of genes induced by cancer chemopreventive agents, are members of this protective system. The NFE2 family transcription factor Nrf2 was found to govern expression of these detoxifying enzymes, and screening for Nrf2-regulated genes has identified many gene categories involved in maintaining cellular redox potential and protection from oxidative damage as Nrf2 downstream genes. Further, studies using Nrf2-deficient mice revealed that these mutant mice showed more susceptible phenotypes towards exposure to environmental chemicals/carcinogens and in oxidative stress related disease models. With the finding that cancer chemopreventive efficacy of indirect antioxidants (enzyme inducers) is lost in the absence of Nrf2, a central role of Nrf2 in the antioxidative protective system has been firmly established. Promising results from cancer prevention clinical trials using enzyme inducers propose that pharmacological interventions that modulate Nrf2 can be an effective strategy to protect tissues from oxidative damage.

• 한국식품위생안전성학회지
• /
• 제12권4호
• /
• pp.315-320
• /
• 1997

Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatic agent. This study was devised to develop a chemopreventive agent from panax ginseng to be able to suppress the genotoxicity and oxidative damage by ractive oxygen species, which are involved with cancer or aging. Ginseng petroleum ether extract (GPE) and one of its fraction, P2, showed an antioxidative effect on the lipid peroxidiphenyl-2-picryl hydrazil (DppH) radical generation. They also showed the suppressive effect of H2O2 or KO2 induced DNA damage by single cell gel electrophoresis (SCGE). Results from our study indicate that GPE and P2 are capable of protecting lipid peroxidation, and oxidative DNA damage. Therefore, GPE and P2 may be useful chempreventive agents which are involved with cancer and aging.

• Preventive Nutrition and Food Science
• /
• 제18권1호
• /
• pp.11-17
• /
• 2013

Dysfunction of endothelial cells is considered a major cause of vascular complications in diabetes. In the present study, we investigated the protective effect of Padina arborescens extract against high glucose-induced oxidative damage in human umbilical vein endothelial cells (HUVECs). High-concentration of glucose (30 mM) treatment induced cytotoxicity whereas Padina arborescens extract protected the cells from high glucose-induced damage and significantly restored cell viability. In addition, lipid peroxidation, intracellular reactive oxygen species (ROS), and nitric oxide (NO) levels induced by high glucose treatment were effectively inhibited by treatment of Padina arborescens extract in a dose-dependent manner. High glucose treatment also induced the overexpressions of inducible nitric oxide synthase (iNOS), cyclooxygenase- 2 (COX-2) and NF-${\kappa}B$ proteins in HUVECs, but Padina arborescens extract treatment reduced the over-expressions of these proteins. These findings indicate the potential benefits of Padina arborescens extract as a valuable source in reducing the oxidative damage induced by high glucose.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
• /
• pp.84-84
• /
• 2002

Abstract To study the status of oxidative DNA damage in Helicobacter pylori infection in more details, gene-specific oxidative DNA damage was investigated by examining oxidative DNA damage to individual genes. This was done by determining the loss of PCR product of a targeted gene before and after gastric mucosal DNA was treated with 8-hydroxyguanine glycosylase, which cleaves DNA at the 8-hydroxyguanine residues.(omitted)

• Environmental Analysis Health and Toxicology
• /
• 제21권2호
• /
• pp.127-138
• /
• 2006

In urban areas, diesel exhaust particles (DEP) are probably a major component of particulate matters, especially in Korea where drive many diesel vehicles. The aim of this study was to investigate genotoxic effects of DEP using single ceil gel electrophoresis. In order to evaluate the mechanisms of DEP genotoxicity, the rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed. Total diesel particles (DEPT) was collected without site fractionation from diesel engine bus and dichloromethane extract was obtained. The organic extract of DEPT revealed DNA damage itself in NIH/3T3 cells. The level of DNA breaks plus oxidative DNA lesions and microsome mediated DNA damage was assessed by modified single cell gel eletrophoresis. DEPT was able to induce oxidative DNA damage as well as microsome mediated DNA damage. Vitamin C as an model antioxidant reduced DNA damage in endonuclase III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor. reduced DNA damage in the presence of S-9 mixture. $DEP_T$ is the sources of oxidative stress, but antioxidants can significantly reduce oxidative DNA dmage. And $DEP_T$ may contain indirect mutagens which can be inhibited by CYP1A1 inhibitors. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) were evaluated for their in vitro antigenotoxic effects. BV and BF showed potent Inhibitory effects against DEPT induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P4501A1 in cell culture.

• 한국환경성돌연변이발암원학회지
• /
• 제25권2호
• /
• pp.71-75
• /
• 2005

Green tea and their major constituents such as catechins are famous materials for their anti-oxidative and anti-carcinogenic activity, but many compounds with reducing power can promote the oxidation in their oxidized form or in the presence of metal ion. We investigated the pro-oxidative effect of the ethanol extract equivalent up to 30mg of dried weight of green tea leaves in four in vitro systems which could be used for detecting DNA damage. Although ethanol extract of green tea did not show significant mutagenicity in Salmonella typhimurium TA102, which is sensitive strain to oxidative stress, it degraded deoxyribose extensively in the presence of $FeCl_3-EDTA$ complex, promoted 8-oxoguanine formation in the live bacteria cell, Salmonella typhimurium TAI04, and cleaved super coiled DNA strand with the help of copper ion. It suggested that green tea, famous anti-oxidative material, can be pro-oxidant according to the condition of extraction or metal existence.