• Applied Biological Chemistry
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• v.48 no.2
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• pp.155-160
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• 2005

Electrolyzed reduced water (ERW), showing extremely negative oxidation-reduction potential, was used to investigate the effects of paraquat-induced damages on DNA from human lymphocyte. The effect of ERW on paraquat-induced oxidative DNA damage in human lymphocytes was evaluated by Comet assay (single-cell gel electrophoresis) quantified as percentage fluorescence in tail. Comet assay has been used widely to assess the level of the DNA damage in individual cells. Lymphocytes were oxidatively challenged with various concentrations of paraquat for 30 min at $37^{\circ}C$, and were then treated with electrolyzed reduced water for 30 min. The oxidative DNA damage by paraquat, as indicated by the fluorescent tail in DNA, increased in a dose-dependent manner. However, oxidative damage of the DNA was almost completely prevented upon treatment with electrolyzed reduced water.

• Korean Journal of Environmental Biology
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• v.38 no.2
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• pp.248-253
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• 2020

The level at which analyses of DNA content might contribute more significantly to the genetic mechanisms of evolution lies in the events of speciation. The object of this study was to investigate the DNA content of abalone (Haliotis discus hannai) and determine the optimal tissue samples for measuring the DNA content of abalone by flowcytometry without fixation. The DNA content (pg/nucleus) of gill tissue (2.5±0.08), which was contaminated with protozoa, was significantly lower than that of muscle tissue (3.2±0.02), mantle tissue (3.2±0.02) (p<0.05), and a standard reference standard, while the DNA contents of muscle tissue and mantle tissue were higher than that of the standard reference. Considering the results of this study, DNA content analysis with flowcytometry is an acute and rapid method by which muscle tissue and mantle tissue are the most appropriate sample for measuring the DNA content of abalone without fixation.

• Journal of Nutrition and Health
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• v.44 no.5
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• pp.366-377
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• 2011

Glutathione S-transferase (GST) is a multigene family of phase II detoxifying enzymes that metabolize a wide range of exogenous and endogenous electrophilic compounds. GSTM1 and GSTT1 gene polymorphisms may account for inter-individual variability in coping with oxidative stress. We investigated the relationships between the level of lymphocyte DNA and antioxidative parameters and the effect on GST genotypes. GSTM1 and GSTT1 were characterized in 301 young healthy Korean adults and compared with oxidative stress parameters such as the level of lymphocyte DNA, plasma antioxidant vitamins, and erythrocyte antioxidant enzymes in smokers and non smokers. GST genotype, degree of DNA damage in lymphocytes, erythrocyte activities of superoxide dismutase, catalase, and glutathione peroxidase (GSH-Px), and plasma concentrations of total radical-trapping antioxidant potential (TRAP), vitamin C, ${\alpha}$- and ${\gamma}$-tocopherol, ${\alpha}$- and ${\beta}$-carotene, and cryptoxanthin were analyzed. Lymphocyte DNA damage assessed by the comet assay was higher in smokers than that in non-smokers, but the levels of plasma vitamin C, ${\beta}$-carotene, TRAP, erythrocyte catalase, and GSH-Px were lower than those of non-smokers (p < 0.05). Lymphocyte DNA damage was higher in subjects with the GSTM1- or GSTT1-present genotype than those with the GSTM1-present or GSTT1- genotype. No difference in erythrocyte antioxidant enzyme activities, plasma TRAP, or vitamin levels was observed in subjects with the GSTM1 or GSTT1 genotypes, except ${\beta}$-carotene. Significant negative correlations were observed between lymphocyte DNA damage and plasma levels of TRAP and erythrocyte activities of catalase and GSH-Px after adjusting for smoking pack-years. Negative correlations were observed between plasma vitamin C and lymphocyte DNA damage only in individuals with the GSTM1-present or GSTT1- genotype. The interesting finding was the significant positive correlations between lymphocyte DNA damage and plasma levels of ${\alpha}$-carotene, ${\beta}$-carotene, and cryptoxanthin. In conclusion, the GSTM1- and GSTT1-present genotypes as well as smoking aggravated antioxidant status through lymphocyte DNA damage. This finding confirms that GST polymorphisms could be important determinants of antioxidant status in young smoking and non-smoking adults. Consequently, the protective effect of supplemental antioxidants on DNA damage in individuals carrying the GSTM1- or GSTT1-present genotypes might show significantly higher values than expected.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.180-180
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• 1996

Previous studies have shown that kainic acid (KA) causes an elevation of hippocampal proenkephalin mRNA level. However, the role of proto-oncogene products, such as c-Fos, c-Jun and Fra proteins in the regulation of KA-induced proenkephalin mRNA increase in the hippocampus has not been well characterized. Thus, in the present study, the effect of cycloheximide (CHX) on KA-induced proenkephalin mRNA and immediate early gene products induction was examined. After pretreating with either vehicle or CHX (20 mg/kg, s.c.) for 30 min, KA (10 mg/kg) was administered s.c. The animals were sacrificed 1,2, or 8 hrs after KA administration. Total RNA and were isolated for Northern blot assay, and proteins were isolated for Western and electrophoretic gel-shift assays. First, we found that CHX inhibited KA-induced proenkephalin mRNA increase without altering intracellular proenkephalin protein level. Secondly, Western blot assays showed that KA increased c-Fos, c-Jun and Fra proteins at 1,2, and 8 hrs and CHX inhibited these immediate early gene products. Finally, electrophoretic gel shift assays revealed that KA increased both AP-1 and ENKCRE-2 DNA binding activities. Furthermore, CHX attenuated KA-induced AP-1 and ENKCRE-2 DNA binding activities. Both AP-1 and ENKCRE-2 DNA binding activities were abolished by cold AP-1 or ENKCRE-2 oligonucleotides, and further reduced by antibodies against c-Fos or c-Jun. Antibody against CREB reduced ENKCRE-2, but not AP-1, DNA binding activity. Our results suggest that on-going protein synthesis is required for elevation of hippocampal proenkephalin mRNA level induced by KA. All c-Fos, c-Jun, and Fra proteins appears to be involved in the regulation of hippocampal proenkephalin mRNA level induced by KA (This study was supported by a grant from KOSEF).

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.25-31
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• 2002

We describe a riboprinting scheme for identification of unknown Acanthamoeba isolates at the species level. It involved the use of PCR-RFLP of small subunit ribosomal RNA gene (riboprint) of 24 reference strains by 4 kinds of restriction enzymes. Seven strains in morphological group I and III were identified at species level with their unique sizes of PCR product and riboprint type by Rsa 1. Unique RFCP of 17 strains in group II by Dde I. Taq I and Hae III were classified into: (1) four taxa that were identifiable at the species level. (2) a subgroup of 4 taxa and a pair of 2 taxi that were identical with each other. and (3) a species complex of 7 taxa assigned to A. castellanii complex that were closely related. These results were consistent with those obtained by 18s rDNA sequence analysis. This approach provides an alternative to the rDNA sequencing for rapid identification of a new clinical isolate or a large number of environmental isolates of Acanthamoeba.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.116-116
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• 2001

The alkaline Comet assay has been used with increasing popularity to investigate the level of DNA damage in terms of strand breaks and alkaline labile sites in biomonitoring studies within the last decade in western countries.(omitted)

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.459-464
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• 1997

The human liver cDNA clone UDPGTh2, encoding a liver UDP-glucuronosyltransferase (UDPGT) was isolated from a .gamma. gt 11 cDNA library by hybridization to mouse transferase cDNA clone, UDPGTm1. UDPGTh2 encoded a 529 amino acid protein with an amino terminus membrane-insertion signal peptide and a carboxyl terminus membrane-spanning region. There were three potential asparagine-linked glycosylation sites at residues 67, 68, and 315. In order to obtain UDPGTh2 protein encoded from cloned human liver UDP-glucuronosyltransferase cDNA, the clone was inserted into the pSVL vector (pUDPGTh2) and expressed in COS 1 cells. The presence of a transferase with Mr-52,000 in transfected cells cultured in the presence of $[^{35}S]$ methionine was shown by immunocomplexed products with goat antimouse transferase IgG and protein A-Sepharose and analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The expressed UDPGT was a glycoprotein as indicated by electrophoretic mobility shift in Mr-3,000-4,000 when expressed in the presence of tunicamycin. The extent of glycosylation was difficult to assess, although one could assume that glycosyl structures incorporated at the level of endoplasmic reticulum were always the core oligosaccharides. Thus, it is likely that at least two moieties inserted can account for the shift of Mr-3,000-4,000. This study demonstrates the cDNA and deduced amino acid sequence of human liver UDP-glucuronosyltransferase cDNA, UDPGTh2.

• Journal of Nutrition and Health
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• v.37 no.6
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• pp.440-447
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• 2004

In this study the in vitro protective effects of several antioxidant vitamins (vitamin C, $\alpha$-tocopherol, $\beta$-carotene), fruits and vegetables (strawberry, tangerine, orange and 100％ orange juice, carrot juice), on the levels of isolated human lymphocyte DNA damage was measured using Comet assay. Comet assay has been used widely to assess the level of the DNA damage in the individual cells. Lymphocytes were pre-treated for 30 minutes with antioxidant vitamins (10, 50, 100, 500 $\mu$M) or fruits$.$vegetables (10, 100, 500, 1000 $\mu$g/ml), an4 then oxidatively challenged with 100 $\mu$M $H_2O$$_2$ for 5 min at 4$^{\circ}C$. The protective effect of antioxidant vitamins against DNA damage at a concentration of 50 $\mu$M were 50％ in vitamin C, 32％ in $\alpha$-tocopherol, whereas, fJ-carotene showed a 55％ protection at a dose as low as 10 $\mu$M. The inhibitory effects of DNA damage by strawberry, tangerine, orange, orange juices, carrot juices were 50 - 60％ with wide ranges of doses. The results of the present study indicate that most the antioxidant vitamins and fruits$.$vegetables juices produced a significant reduction in oxidative DNA damage.

• The Korea Journal of Herbology
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• v.22 no.1
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• pp.7-12
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• 2007

Objectives : In Alzheimer's disease(AD), free radical oxidative stress caused by amyloid beta-peptide may lead to DNA damage, neuronal dysfunction, neurotoxicity and cell death, Hwangryunhaedok-tang(HHT) is traditionally used for the treatment of pyrogenetic diseases. To develop a new anti-AD drug from natural herb, HHT was selected and extracted in this study. Methods : The antioxidant activities of HHT water extract powder were examined by hydroxyl radical-induced DNA strand nicking assay, and antioxidative enzymes expression assay in H4IIE cell. In addition, HHT was examined for the inhibitory effect on the acetylcholinesterase(AChE) using by Ellman's coupled assay. Results: The HHT exhibit DNA protective effect in the hydroxyl radical-induced DNA Strand nicking assay, mRNA expression of superoxide dismutase and glutathione peroxidase were recovered at a normal level by HHT treatment in H4IIE cell. Furthermore, water extract of HHT showed inhibitory effect on AChE activity. Conclusion : These results suggest that HHT may be effective in delaying and preventing AD progression related to the free radical-induced DNA damage and AChE activity.

• Biomedical Science Letters
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• v.11 no.2
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• pp.227-235
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• 2005

It has been reported that endurance performance is influenced by various environmental and genetic factors. In view of an important role of human mitochondrial DNA (mtDNA) as a candidate for endurance performance, this study focused on the relationships between $VO_{2max}$ value as a measure of endurance performance or other associated phenotypes and four mtDNA restriction fragment length polymorphisms (RFLPs) (Bam HI, Hinc II1, Hinc II2 and Nci I) in the NADH dehydrogenase subunit 5 and one (Kpn I) in the D-loop region of mtDNA. MtDNA was purified from buffy coat in human peripheral blood, and PCR-RFLP analysis was performed to estimate the allele frequencies of each polymorphism in the mtDNA. There were no significant differences in allele distributions of all polymorphisms studied between male athletes and controls, respectively (P>0.05). However, the Kpn I polymorphism was significantly associated with diastolic blood pressure level in male athletes, respectively (P<0.05). Therefore, our results suggest that this polymorphism might be one of the factors modifying inter-individual difference in cardiovascular risk. Further studies using larger sample size will be required to generalize these results from the study described herein.