• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.261-269
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• 2009

To evaluate the effect of antioxidant on the cytotoxicity induced by oxidative stress of reactive oxygen species (ROS) in cultured human skin melanocytes, colorimeric assay of XTT and tyrosinase activity assay were adopted after human skin melanocytes were preincubated for 2 hours in the media containing various concentrations of superoxide dismutase (SOD) before the treatment of hydrogen peroxide. Light microscopic study was carried out in same cultures. The results of this study were as follows 1. Cell viability of human skin melanocytes was significantly decreased by 30 and $40{\mu}M$ of hydrogen peroxide($H_2O_2$), respectively. 2. XTT50 was determined at $30{\mu}M$ after human skin melanocytes were treated with $10{\sim}40{\mu}M$ of hydrogen peroxide for 6 hours. 3. The cell viability of cultured human skin melanocytes pretreated with SOD was increased than that of cultured human skin melanocytes treated with $H_2O_2$ dose-dependently. 4. In tyrosinase activity of human skin melanocytes, the cell treated with SOD showed brown stain compared with $H_2O_2$ treated cells, dark stain. 5. In light microscopy, cultured human skin melanocytes exposed to $H_2O_2$ showed morphological changes such as the decreased cell number and cytoplasmic processes, compared with control. 6. In light microscopy, cultured human skin melanocytes pretreated with SOD showed the increase of cell number and cytoplasmic processes compared with $H_2O_2-treated$ group. From these results, it is suggested that oxidative stress of ROS such as $H_2O_2$ has cytotoxicity by showing the decreased cell viability, the increased tyrosinase activity and mophological changes of the decreased cell number and cytoplasmic processes. While, antioxidant like SOD was effective in the prevention of oxidative stress-mediated cytotoxicity by the increased cell viability, decreased tyrosinase activity and the protection of degenerative morphological changes in cultured human skin melanocytes.

• Journal of Life Science
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• v.10 no.1
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• pp.107-113
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• 2000

This study carried out to investigate activities of the superoxide dismutase(SOD), peroxidase(POD) and diterpene cyclase of rice plant treated by environmental stress conditions. The rice leaves of Ilpum was shown to have the most highest specific activity of POD. POD activity in the susceptible cv. Ilpum and Hwasung during the disease progress show a increase, while for a decreasing activity in the resistant cv. Dasan. SOD activity of rice plants treated by chitosan were increased as the treatment concentration increased. At the chitosan application, the SOD activity in the susceptible cv. Hwansung at the rice leaves 14days after treatment was higher in treatment than chitosan-untreated control. The activity of POD in the susceptible cv. Ilpum decreased as long as UV-B irradiation, while that in the resistant cv. Dasan increased. Futhermore, activity of that in Dasan were similar to as time on UV irradiation, Hwasung showed two times higher than untreated control at 40 minutes after UV-B exposure. The activity of diterpene cyclase in rice plants inoculated with Pyricularia oryzae has much higher tendency than UV-B irradiation. The activity of diterpene cyclase in the rice leaves gradually increased until 5 days after inoculation with Pyricularia oryzae.

• YAKHAK HOEJI
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• v.32 no.4
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• pp.287-293
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• 1988

Oxygen free radical have recently been found to mediate cell injury after ischemia in the kidney. The purpose of our study was to determine whether selenium had an effect on damge mediated by oxygen free radical in inorganic mercury induced renal failure, toxic model of renal failure. Toxic renal failure model was produced by subcutaneous injection of mercuric chloride (4mg/kg) once a day for 7 consecutive days. In additionally, coadministration of sodium selenite (1mg/kg) was performed by the same condition. As a consequence of this study, we were able to detect partially unequivocal role of selenium as below dipicted. The combination of sodium selenite showed that markedly inhibited production of superoxide radical in mercuric chloride alone. On the other hand, combined sodium selenite was unable to enhance against significantly lowered superoxide dismutase activity after mercuric chloride insult. However, simultaneous administration of sodium selenite was inclined to induce mitochondrial superoxide dismutase and catalase.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.149-149
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• 1993

목적:동식물세포에는 superoxide(0$_{-2}$)의 불균화 반응을 촉매하는 superoxide dismutase (SOD)가 존재한다. 이 효소의 생리적 의의는 지금까지도 명확하게 되어있지 않는면이 많지만, 그 의의를 명확하게 하기위해서도 측정법의 확립이 필요하다. 방법: SOD측정 방법으로는 1) Cytochrome C method 2) Nitroblue tetrazoliun method (NBT법) 3) 면역학적 방법 4) 화학발광법 등이 있다. 실험 재료는 흰쥐, mouse, 토끼의 간을 이용하였으며, 또한, 노화 및 암세포를 이용한 방법을 이용하였다. 결과: Cytochrome C 방법을 통해서 각 장기조직 (신장, 간장, 폐)에서 SOD를 측정하였으며 SOD 활성이 낮은 암조직이나 배양세포에서는 NBT 방법이 측정방법으로 적합한 것으로 나타났으며 ,간장세포내에서의 SOD의 존재부위를 확인하는 방법으로는 면역 황금 표지방법을 사용하므로 간장 mitochondria 내에 Cu, Zn-SOD가 존재함을 알 수 있었다.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.229-239
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• 1997

The superoxide anion radical$(O_2)$ poses a threat to macromocules and cell organelles of the living cells. This toxicity damage to all groups of proteins results in loss of enzyme function concerned with metabolism and ion transport, and peroxidation of unsaturated fatty acids and cholesterol results in a change of permeability characteristics of the membrane, and oxidative of nucleic acids results in genomic damage and thereby cause mutation, potential carcinogenesis and somatic damage that produce cellular aging Superoxide dismutase(SOD) has received substantial attention as a potential therapeutic agent. It has been investigated as a possible agent for the prevention of ontogenesis, the reduction of cytotoxic effect of anticancer drugs, and protection against damage in ischemic tissue. It is suggest that $O_2$ is concerned with cellular aging, thereafter we need to investigate herb that activated to SOD.

• BMB Reports
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• v.30 no.1
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• pp.60-65
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• 1997

Expression of human Cu.Zn-superoxide dismutase (SOD) with activity comparable to human erythrocyte enzyme was achieved in E. coli B21(DE3) by using the pET-17b expression vector containing a T7 promoter. Recombinant human SOD was found in the cytosol of disrupted bacterial cells and represented > 25% of the total bacterial proteins. The protein produced by the E. coli cells was purified using a combination of ammonium sulfate precipitation, Sephacryl S-100 gel filtration and DEAE-Sephacel ion exchange chromatography. The recombinant Cu,Zn-SOD and human erythrocyte enzyme were compared using dismutation activity, SDS-PAGE and immunoblotting analysis. The mass of the subunits was determined to be 15,809 by using a electrospray mass spectrometer. The copper specific chelator. diethyldithiocarbamate (DOC) reacted with the recombinant Cu,Zn-SOD. At $50{\mu}M$ and $100{\mu}M$ concentrations of DOC, the dismutation activity was not inhibited for one hour but gradually reduced after one hour. This result suggests that the reaction of DOC with the enzyme occurred in two distinct phases (phase I and phase II). During phase I of this reaction, one DOC reacted with the copper center, with retention of the dismutation activity while the second DOC displaced the copper, with a loss of activity in phase II.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.79-84
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• 2001

To assess resistance of transgenic tobacco plants which overexpress superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts to water stress, changes in leaf water potential, turgor potential, stomatal conductance and transpiration rate were measured. Leaf water potential in all plants remained high up to day 4 after withholding water but thereafter decreased markedly. In spite of a remarkable decrease in leaf water potential, some of transgenic plants maintained higher turgor potential compared with control plant on day 12. In particular, the transgenic plant expressing MnSOD showed an outstanding maintenance in turgor pressure by osmotic adjustment throughout the experiment, resulting in high stomatal conductance and transpiration rate. However, among transgenic plants, osmotic potential was reduced more effectively in multiple transformants such as the double transformant expressing both MnSOD and APX, and the triple transformant expressing CuznSOD, MnSOD and APX than single transformants. Consequently, further research is needed to get general agreement on the tolerance of transgenic plants to water stress at different growth stages for each transgenic plant.

• Journal of Photoscience
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• v.8 no.1
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• pp.13-17
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• 2001

Cucumber leaves subjected to light chilling stress exhibit a preferential inactivation of photosystem(PS) I relative to PSII, resulting in the photoinhibition of photosynthesis. In light chilled cucumber leaves, Cu/Zn-Superoxide dismutase(SOD) is regarded as a primary target of the light chilling stress and its inactivation is closely related to the increased production of reactive oxygen species. In the present study, we further explored that inactivation of PSI in cucumber leaves is not a light chilling specific, but general to various oxidative stresses. Oxidative stress in cucumber leaves was induced by treatment of methylviologen(MV), a producer of reactive oxygen species in chloroplasts. MV treatment decreased the maximal photosynthetic O$_2$ evolution, resulting in the photoinhibition of photosynthesis. The photoinhibition of photosynthesis was attributable to the decline in PSI functionality determined in vivo by monitoring absorption changes around 820 nm. In addition, MV treatment inactivated both antioxidant enzymes Cu-Zn-superoxide dismutase and ascorbate peroxidase known sensitive to reactive oxygen species. From these results, we suggest that chloroplast antioxidant enzymes are the primary targets of photooxidative stress, followed by subsequent inactivation of PSI.

• Plant Resources
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• v.7 no.3
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• pp.163-169
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• 2004

To investigate the defense mechanism against the abiotic stress, a cDNA clone encoding a CuZn superoxide dismutase (CuZnSOD) protein was isolated from a cDNA library prepared from tabroot mRNAs of Codonopsis lanceolata. The eDNA, designated ClSODCc, is 799 nucleotides long and has an open reading frame of 459 bp with a deduced amino acid sequence of 152 residues. The deduced amino acid sequence of ClSODCc matched to the previously reported CuZnSODs. Consensus amino acid residues (His-45, -47, -62, -70, -79, -119 and Asp-82) were involved in Cu-, Cu/Zn-, and Zn- binding ligands. The deduced amino acid sequence of ClSODCc showed high homologies (82％-86％) regardless of species. Expression of ClSODCc by oxidative stress was increased up to 1 h after treatment and declined gradually. Much earlier and stronger expression of ClSODCc was observed in the cold stress treatment.

• Molecules and Cells
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• v.21 no.1
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• pp.161-165
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• 2006

Dichlorodihydrofluorescein ($DCFH_2$) is a widely used probe for intracellular $H_2O_2$. However, $H_2O_2$ can oxidize $DCFH_2$ only in the presence of a catalyst, whose identity in cells has not been clearly defined. We compared the peroxidase activity of Cu,Zn-superoxide dismutase (CuZnSOD), cytochrome c, horseradish peroxidase (HRP), $Cu^{2+}$, and $Fe^{3+}$ under various conditions to identify an intracellular catalyst. Enormous increase by bicarbonate in the rate of $DCFH_2$ oxidation distinguished CuZnSOD from cytochrome c and HRP. Cyanide inhibited the reaction catalyzed by CuZnSOD but accelerated that by $Cu^{2+}$ and $Fe^{3+}$. Oxidation of $DCFH_2$ by $H_2O_2$ in the presence of a cell lysate was also enhanced by bicarbonate and inhibited by cyanide. Confocal microscopy of $H_2O_2$-treated cells showed enhanced DCF fluorescence in the presence of bicarbonate and attenuated fluorescence for the cells pre-incubated with KCN. Moreover, DCF fluorescence was intensified in CuZnSOD-transfected HaCaT and RAW 264.7 cells. We propose that CuZnSOD is a potential intracellular catalyst for the $H_2O_2$-dependent oxidation of $DCFH_2$.