• BMB Reports
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• v.39 no.4
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• pp.452-456
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• 2006

To elaborate the peroxidase activity of cytochrome c in the generation of free radicals from $H_2O_2$, the mechanism of DNA cleavage mediated by the cytochrome c/$H_2O_2$ system was investigated. When plasmid DNA was incubated with cytochrome c and $H_2O_2$, the cleavage of DNA was proportional to the cytochrome c and $H_2O_2$ concentrations. Radical scavengers, such as azide, mannitol, and ethanol, significantly inhibited the cytochrome c/$H_2O_2$ system-mediated DNA cleavage. These results indicated that free radicals might participate in the DNA cleavage by the cytochrome c and $H_2O_2$ system. Incubation of cytochrome c with $H_2O_2$ resulted in a time-dependent release of iron ions from the cytochrome c molecule. During the incubation of deoxyribose with cytochrome c and $H_2O_2$, the damage to deoxyribose increased in a time-dependent manner, suggesting that the released iron ions may participate in a Fenton-like reaction to produce $\cdot$OH radicals that may cause the DNA cleavage. Evidence that the iron-specific chelator, desferoxamine (DFX), prevented the DNA cleavage induced by the cytochrome c/$H_2O_2$ system supports this mechanism. Thus we suggest that DNA cleavage is mediated via the generation of $\cdot$OH by a combination of the peroxidase reaction of cytochrome c and the Fenton-like reaction of free iron ions released from oxidatively damaged cytochrome c in the cytochrome c/$H_2O_2$ system.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.517-518
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• 2003

• Bulletin of the Korean Chemical Society
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• v.18 no.1
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• pp.117-119
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• 1997

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.130-138
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• 2011

In this study, we evaluated the protective effects of the hot water extract from red bean (Phaseolus angularis) against oxidative DNA and cell damage induced by hydroxyl radical. The antioxidant activities were evaluated by hydroxyl radical and hydrogen peroxide scavenging assay, and $Fe^{2+}$-chelating assay. Although the extract with hot water didn't scavenge the hydroxyl radical, it removed and chelated hydrogen peroxide and ferrous iron necessary for the induction of hydroxyl radical by 71% and 64% at 200 ${\mu}g/ml$, respectively. Its protective effect on oxidative DNA damage was carried using ${\Psi}$X-174 RF I plasmid DNA comparing the conversion level of supercoiled form of the plasmid DNA into open-circular form and linear form and the expression level of phospho-H2AX in NIH 3T3 cells. In ${\Psi}$X-174 RF I plasmid DNA cleavage assay, it inhibited oxidative DNA damage by 96% at 200 ${\mu}g/ml$. Also, it decreased the expression of phospho-H2AX by 50.1% at 200 ${\mu}g/ml$. Its protective effect against oxidative cell damage was measured by MTT assay and the expression level of p21 protein in NIH 3T3 cells. In MTT assay for the protective effect against the oxidative cell damage, it inhibited the oxidative cell death and the abnormal cell growth induced by hydroxyl radical. Also, it inhibited p21 protein expression by 98% at 200 ${\mu}g/ml$. In conclusion, the results of the present studies indicate that hot water extract from red bean exhibits antioxidant properties and inhibit oxidative DNA damage and the cell death caused by hydroxyl radical.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.139-145
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• 2009

The purpose of this study was to evaluate the effects of the water extract of Samultang (SMT), a Chinese herb, on apoptotic cell death by $H_2O_2$-induced oxidative stress in SK-N-M C cells. A nuclear fragmentation was observed via fluorescence imaging 12 h after exposure to 30 ${\mu}M$ $H_2O_2$ and DNA laddering was detected via agarose electrophoresis gel. In addition, increases in sub-G1 phase and cleavage of the PARP protein were observed. However, treatment with SMT for 2 h prior to $H_2O_2$ exposure significantly reduced apoptotic cell death induced by incubation with 30 ${\mu}M$ $H_2O_2$ in SK-N-MC cells. Pre-incubation with water extract of SMT for 2 h prevented the $H_2O_2$-induced decrease in mitochondrial transmembrane potential. SMT also attenuated the increase in caspase-3 activity and the breakdown of PARP protein caused by $H_2O_2$-induced oxidative stress. These results suggest that the water extract of SMT provides inhibition of apoptotic cell death against oxidative injury in SK-N-MC cells.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.2
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• pp.86-92
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• 2019

The aim of this study was to investigate effects of hyaluronidase during IVM on oocyte maturation, oxidative stress status, expression of cumulus expansion-related (PTX, pentraxin; GJA1, gap junction protein alpha 1; PTGS2, prostaglandin-endoperoxide synthase 2) and fatty acid metabolism-related (FADS1, delta-6 desaturase; FADS2, delta-5 desaturase; PPARα, peroxisome proliferator-activated receptor-alpha) mRNA, and embryonic development of porcine oocytes. The cumulus-oocyte complexes (COCs) were incubated with 0.1 mg/mL hyaluronidase for 44 h. Cumulus expansion was measured at 22 h after maturation. At 44 h after maturation, nuclear maturation, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels were measured. Gene expression in cumulus cells was analyzed using real time PCR. The cleavage rate and blastocyst formation were evaluated at Day 2 and 7 after insemination. In results, expansion of cumulus cells was suppressed by treatment of hyaluronidase at 22 h after maturation. Intracellular GSH level was reduced by hyaluronidase treatment (p < 0.05). On the other hand, hyaluronidase increased ROS levels in oocytes (p < 0.05). Only PTGS2 mRNA was enhanced in COCs by hyaluronidase (p < 0.05). Population of oocytes reached at metaphase II stage was higher in control group than hyaluronidase treated group (p < 0.05). Both of cleavage rate and blastocyst formation were higher in control group than hyaluronidase group (p < 0.05). Our present results showed that developmental competence of porcine oocytes could be reduce by hyaluronidase via inducing oxidative stress during maturation process and it might be associated with prostaglandin synthesis. Therefore, we suggest that suppression of cumulus expansion of COCs could induce oxidative stress and decrease nuclear maturation via reduction of GSH synthesis and it caused to decrease developmental competence of mammalian oocytes.

• Journal of Animal Reproduction and Biotechnology
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• v.39 no.1
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• pp.48-57
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• 2024

Background: Cadmium (Cd) is toxic heavy metal that accumulates in organisms after passing through their respiratory and digestive tracts. Although several studies have reported the toxic effects of Cd exposure on human health, its role in embryonic development during preimplantation stage remains unclear. We investigated the effects of Cd on porcine embryonic development and elucidated the mechanism. Methods: We cultured parthenogenetic embryos in media treated with 0, 20, 40, or 60 µM Cd for 6 days and evaluated the rates of cleavage and blastocyst formation. To investigate the mechanism of Cd toxicity, we examined intracellular reactive oxygen species (ROS) and glutathione (GSH) levels. Moreover, we examined mitochondrial content, membrane potential, and ROS. Results: Cleavage and blastocyst formation rates began to decrease significantly in the 40 µM Cd group compared with the control. During post-blastulation, development was significantly delayed in the Cd group. Cd exposure significantly decreased cell number and increased apoptosis rate compared with the control. Embryos exposed to Cd had significantly higher ROS and lower GSH levels, as well as lower expression of antioxidant enzymes, compared with the control. Moreover, embryos exposed to Cd exhibited a significant decrease in mitochondrial content, mitochondrial membrane potential, and expression of mitochondrial genes and an increase in mitochondrial ROS compared to the control. Conclusions: We demonstrated that Cd exposure impairs porcine embryonic development by inducing oxidative stress and mitochondrial dysfunction. Our findings provide insights into the toxicity of Cd exposure on mammalian embryonic development and highlight the importance of preventing Cd pollution.

• The Korea Journal of Herbology
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• v.27 no.6
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• pp.7-13
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• 2012

Objectives : Reactive oxygen species (ROS) have been associated with pathogenic processes including carcinogenesis through direct effect on DNA directly and by acting as a tumor promoter. Therefore, it has been regarded that ROS may be a major target for cancer prevention. The root of Paeonia lactiflora pall (PL), a traditional Chinese herb, has been a component of effective prescriptions for treatment of liver disease. Also, there are some reports about the antioxidant activities of the extracts from PL. However, little has been known about the effects of PL against oxidative damage. This work aimed to elucidate the anti-oxidant effects of Paeonia lactiflora pall (PL) in the non-cellular system and cellular system. Methods : Antioxidant activities of PL were evaluated by hydroxyl radical scavenging assay and $Fe^{2+}$ chelating assay. Anti-oxidative effect of PL was evaluated by ${\varphi}X$-174 RF I plasmid DNA cleavage assay in non-cellular system. In addition, DNA migration assay, expression level of phospho-H2AX, MTT assay and lipid peroxidation assay were performed for evaluate the anti-oxidative effect of PL in cellular system. Results : PL had a dose-dependent hydroxyl radical scavenging and $Fe^{2+}$ chelating capacity. In addition, PL inhibited oxidative DNA and cell damage induced by hydroxyl radical in non-cellular system and cellular system. Conclusion : Taken together, P. lactiflora pall may be possible for the application to a potential drug for treating the oxidative diseases such as cancer.

• YAKHAK HOEJI
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• v.36 no.3
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• pp.250-254
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• 1992

Benzo[C]phenanthidine alkaloids were found to exhibit considerably strong antileukemic activies. These alkaloids have been shown to be biosynthesized from the corresponding alkaloids throung an oxidative $C_6-N$ bond cleavage followed by recyclization between $C_6\;and\;C_{13}$ position of the protoberberine. Recently we have achieved the biomimetic transformation of protoberberine alkaloid, berberine into benzo[C]phenanthridine alkaloid, chelerythrine.

• Journal of the Korean Wood Science and Technology
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• v.31 no.3
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• pp.11-16
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• 2003

On nitrobenzene oxidation of aspen, spruce, and knauf wood meals gave rise to vanilline, syrigaldehyde, p-hydroxybenzoaldehyde, vanillic acid, and other minor oxidation products. The phenolic aldehydes (p-hydroxybenzaldehyde, vanilline, and syringaldehyde) are derived from oxidative degradation of the corresponding 4-hydroxyphenylpropane units and their ethers. The lignin content of knauf wood meals was different as the concentration of NaOH solution and cooking temperature. The lignin contents of aspen, spruce, and knauf wood meals were decreased as laccase treatment. The laccase caused C-oxidation, demethylation, cleavage in phenolic groups and C-C cleavage in syrigyl structures.