• Title, Summary, Keyword: antioxidant system

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Oxidative stress and the antioxidant enzyme system in the developing brain

  • Shim, So-Yeon;Kim, Han-Suk
    • Clinical and Experimental Pediatrics
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    • v.56 no.3
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    • pp.107-111
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    • 2013
  • Preterm infants are vulnerable to the oxidative stress due to the production of large amounts of free radicals, antioxidant system insufficiency, and immature oligodendroglial cells. Reactive oxygen species (ROS) play a pivotal role in the development of periventricular leukomalacia. The three most common ROS are superoxide ($O2^{\cdot-}$), hydroxyl radical ($OH^{\cdot}$), and hydrogen peroxide ($H_2O_2$). Under normal physiological conditions, a balance is maintained between the production of ROS and the capacity of the antioxidant enzyme system. However, if this balance breaks down, ROS can exert toxic effects. Superoxide dismutase, glutathione peroxidase, and catalase are considered the classical antioxidant enzymes. A recently discovered antioxidant enzyme family, peroxiredoxin (Prdx), is also an important scavenger of free radicals. Prdx1 expression is induced at birth, whereas Prdx2 is constitutively expressed, and Prdx6 expression is consistent with the classical antioxidant enzymes. Several antioxidant substances have been studied as potential therapeutic agents; however, further preclinical and clinical studies are required before allowing clinical application.

A Study on Antioxidant System in Cataract Patients (한국인 백내장환자의 항산화 체계에 관한 연구)

  • 고영숙;홍영재;정혜연;김수연;이양자
    • Journal of Nutrition and Health
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    • v.35 no.2
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    • pp.229-236
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    • 2002
  • Cataracts are the leading cause of blindness worldwide and are characterized by increased opacity of the lens that significantly diminishes visual acuity. It has been suggested that increased risk of lens opacities are associated with age, exposure to sunlight, diabetes, smoking, and poor nutrition. Antioxidant nutrients have born demonstrated to protect the lens membrane and protein against damage due to oxidative stress. The purpose of this study was to investigate the antioxidant system in the blood of cataract patients. The status of the blood antioxidant system was evaluated based on the levels of antioxidant vitamins and minerals as well as glutathione peroxidase (GSH-Px) and malondialdehyde (M7A) activity in 34 patients with cataracts (17 male and 17 female) and 45 control subjects (20 male and 25 female). After adjusting for age, the results showed significantly lower levels of antioxidant vitamins such as lycopene (M : p < 0.05, F: p < 0.01), zeaxanthin (F: p < 0.01), ${\gamma}$-tocopherol (F: p < 0.01) and ascorbic arid (M: p < 0.05) in the cataract patients than in the control subjects. In contrast, the concentration of cryptoxanthin (F : p < 0.07) showed a significantly higher value in the cataract patients. The serum level of the antioxidant mineral Zn (M : p < 0.01) was found to be significantly lower in the cataract patients while the ratio of cu/zn appeared significantly higher (M : p < 0.05). Significantly higher (M : p < 0.01, F: p < 0.05) concentrations of MDA in serum was found in the cataract patients as compared to the control subjects. GSH-Px activity was significantly lower (F: p < 0.05) in 71e cataract patients. In conclusion, the antioxidant system may play an important roll in cataract creation. Further studies are needed to clarify the mechanisms underlying these findings and to establish preventive measures with an emphasis on antioxidant nutrition for cataract patients.

The Effect of Antioxidant-complex on Oxygen Free Radical Generating and Scavenging System in Rats

  • Doh Seong-Tak;Lee Sang-Il
    • Biomedical Science Letters
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    • v.12 no.1
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    • pp.49-52
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    • 2006
  • To elucidate the effect of antioxidant complex containing $\beta-carotene$, vitamin E, vitamin C, Ginkgo Biloba leaf extract and selenium on oxygen :tree radical production and detoxification system, rats were fed normal diet and normal diet with antioxidant complex 0.1%, 0.3% and 0.5% for 3 weeks. Feed efficiency ratio, changes in body weight, weight gain and amounts of feces of rat are similar in four groups. Liver weight per body weight and hepatic lipid peroxide weight increased in 0.5% group. However, hepatic glutathione contents in all antioxidant complex added groups were significantly increased compare with normal control group. On the other hand, the activity of xanthine oxidase was a little increased due to the amounts of antioxidant complex. Superoxide dismutase and gutathione peroxidase activity of 0.1% antioxidant complex added group were increased about $10{\sim}20%$ in comparison to normal control group. These results suggest that the supplementation of antioxidant complex 0.1% to basal diet may reduce the hepatic damage caused by free radicals.

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Effect of Myricetin Combined with Taurine on Antioxidant Enzyme System in B16F10 Cell (Myricetin과 Taruine의 병용 투여가 B16F10 세포의 항산화 효소계에 미치는 영향)

  • Yu, Ji-Sun;Kim, An-Keun
    • YAKHAK HOEJI
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    • v.50 no.1
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    • pp.58-63
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    • 2006
  • The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress damage. To determine whether myricetin or myricetin/taurine can exert antioxidative effects not only by modulating the AOE system directly but also by scavenging free radical, we investigated the influence of the myricetin and taurine on cell viability ROS level, activities of different antioxidant enzyme, and the expression of different antioxidant enzyme. As results, the cell viability showed inhibition of the proliferation with treatment of 'myricetin' or 'myricetin with taruine', respectively, with dose-dependent manner. Compared to control, the treatment of 'myricetin' decreased activities and gene expressions of superoxide dismutase (SOD), and glutathione peroxidase (GPx). However, combined treatment of 'myricetin with taurine' increased activities and gene expressions of the SOD, GPx, and catalase (CAT). In addition, the combined treatment of 'myricetin with taurine' somewhat decreased ROS levels, compared to the treatment of 'myricetin'. In conclusion, our study provides that the combined treatment of different antioxidants can enhance antioxidant effects.

Photodynamic and Antioxidant Activities of Divalent Transition Metal Complexes of Methyl Pheophorbide-a

  • Yoon, Il;Park, Ho-Sung;Cui, Bing Cun;Li, Jia Zhu;Kim, Jung-Hwa;Lkhagvadulam, Byambajav;Shim, Young-Key
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.2981-2987
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    • 2011
  • A comparative study of the photodynamic and antioxidant activities of methyl pheophorbide-a (MPa, 1) and its transition metal(II) complexes (2-5) is described. Four transition metal complexes (palladium(II): 2, zinc(II): 3, cobalt(II): 4 and copper(II): 5) of MPa were prepared by reaction between the corresponding transition metal and 1, respectively, and were characterized by $^1H$-NMR and UV-vis spectroscopic and mass spectrometric analyses. In vitro results show a photodynamic therapy (PDT) efficacy with A549 cells might be attributed to a heavy atom effect of the transition metal complexes of MPa. Among them, 4 and 5 showed higher photodynamic activity than that of 1 at the concentration of 5 ${\mu}M$ at 24 h incubation after photoirradiation. The images of morphological change for 2-5 show evidence for the PDT effect with A549 cells. And the all transition metal complexes of MPa showed higher antioxidant activity than that of MPa, in which 4 showed the highest antioxidant activity.

Evaluation of Different Methods of Antioxidant Measurement

  • Yoo, Kyung-Mi;Kim, Dae-Ok;Lee, Chang-Yong
    • Food Science and Biotechnology
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    • v.16 no.2
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    • pp.177-182
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    • 2007
  • The beneficial effects of fruits, vegetables, and beverages on human health have been attributed to their antioxidant activities. Therefore, antioxidant activity of food products is recognized as one of the important parameters in determining their functional values. Until now, antioxidant activity has been measured by various chemical and biological methods; however, many factors confound the reliability and reproducibility of measurements of antioxidant activity of food. In vitro methods may provide a useful indication of antioxidant activity but their results may not translate to the human biological system, while in vivo tests are difficult to carry out due to the intricate processes of uptake, cellular transportation, and metabolism of individual antioxidant components. Therefore, as long as these limitations exist, our best option is to measure the antioxidant activity in food directly. This review briefly summarizes currently available methods for the measurement of antioxidant activity in food and examines their respective validity.

Antioxidative Activity of Ulmi cortex Extract (유백피(Ulmi cortex) 추출물의 항산화 활성)

  • 이경행;전은경;유시영;오만진
    • Korean Journal of Food Preservation
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    • v.7 no.4
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    • pp.373-379
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    • 2000
  • The Ulmi corex extract was prepared using various solvents to investigate the availability as a natural antioxidant. The extracts were added to lard emulsion and the antioxidant activities were compared. The extract that had a greater antioxidant activity was fractionized. Then the antioxidant activity and substrate specificity of the fraction were examined and optimum concentration of addition was determined. To observe the antioxidative effect of the fraction in vivo, an inhibition rate of lipid peroxidation from which might be derived was measured using a microsome in rat's liver. Among the extracts of Ulmi cortex, the extract from water had the best antioxidant activity, and the addition of 0.05% (w/w) of ethyl acetate fraction showed similar antioxidant activity to a synthetic antioxidant, butylated hydroxyanisole(BHA). Ethyl acetate fraction (0.05%, w/w) also presented the antioxidative effect in lard, soybean oil, palm oil, and com oil. The inhibition of lipid peroxidation in liver microsome showed feater in the ethyl acetate fraction than caffeic acid in both nonenzymatic peroxidation (Fe$\^$++/ascorbate system) and enzymatic peroxidation (Fe$\^$++/-ADP/NaDPH system).

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Selective Stimulating Effect of Flavonoids on the Antioxidant Defense System in Normal and Transformed Hepatic Cell Lines

  • Kim, Beom-Tae;Lee, Jeong-Chae
    • Natural Product Sciences
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    • v.10 no.6
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    • pp.296-301
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    • 2004
  • Previously, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein, here named RCMF $({\underline{R}}VS\;{\underline{c}}hloroform-{\underline{m}}ethanol\;{\underline{f}}raction)$, was prepared from a crude acetone extract of Rhus verniciflua Stokes (RVS) which is traditionally used as a food additive and as an herbal medicine. In this study, we evaluated the effects of RCMF on the antioxidant defense system using embryonic normal hepatic cell line (BNL CL.2) and its SV40-mediated transformed cell line (BNL SV A.8). This study demonstrates that RCMF selectively stimulated the antioxidant defense system of normal cells, as BNL CL.2 cells proved to be more sensitive to RCMF-mediated increases of superoxide dismutase, catalase, glutathione, and glutathione reductase than BNL SV A.8 cells. In particular, RCMF caused a significant increase in the malonaldehyde content of BNL SV A.8 cells, which is believed to be closely associated with cytotoxicity of RCMF and RCMF-mediated growth inhibition. Collectively, our findings suggest that the flavonoid fraction, RCMF, selectively stimulates the antioxidant defense system in normal rather than hepatic tumor cells.

Increase of Antioxidant Activities of Egg White Protein Hydrolysate by Fractionation without Using Toxic Chemicals

  • Park, Eun Young;Sato, Kenji
    • Culinary science and hospitality research
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    • v.24 no.2
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    • pp.103-111
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    • 2018
  • The objectives of the present study were to examine the antioxidant activity of autofocusing fractions from egg white protein hydrolysates and obtain higher antioxidant peptide fraction, which could be applied to the food model system. Alkaline protease hydrolysate of egg white protein exerted higher antioxidant activities than other protein hydrolysates and were fractionated on the basis of the amphoteric nature of sample peptides by preparative isoelectric focusing without toxic solvents and reagents, which is termed autofocusing. Neutral and basic fractions showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than the acidic fractions. The acidic and neutral fractions showed higher hydroxyl (OH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) values than the basic fractions. The acidic fractions showed higher metal chelating activity than basic fractions. Antioxidant activities of some autofocusing fractions except for ORAC showed higher compared to the crude hydrolysate. These results suggest that peptides fractions from egg white protein are effective antioxidant, and that autofocusing could be useful to increase antioxidant activity for application to food system.

Effect of Myricetin on mRNA Expression of Different Antioxidant Enzymes in B16F10 Murine Melanoma Cells (B16F10 Murine Melanoma Cell에서 Myricetin이 항산화효소의 m-RNA 발현에 미치는 영향)

  • Yu Ji Sun;Kim An Keun
    • YAKHAK HOEJI
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    • v.49 no.1
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    • pp.86-91
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    • 2005
  • Flavonoids are class of polyphenolic compounds widely distributed in the plant kingdom, which display a variety of biological activities, including antiviral, antithrombotic, antiinflammatory, antihistaminic, antioxidant and free-radica 1 scavenging abilities. The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress insults. To determine whether flavonoid, myricetin can exert antioxidative effects not only directly by modulating the AOE system but also scavenging free radical, we investigated the influence of the flavonoid myricetin on cell viability, different antioxidant enzyme activities, ROS level and the expression of different antioxidant emzyme in B16F10 murine melanoma cells. Myricetin in a concentration range from 6.25 to $50\;{\mu}M$ decreased superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities, but catalase (CAT) activity was increased. In the myricetin-treated group, ROS levels were decreased dose-dependently. Antioxidant enzyme expression was measured by RT-PCR. Myricetin treatment of B16F10 cells increased catalase expression. Expression levels of copper zinc superoxide dismutase (CuZn SOD) were not affected by exposure of myricetin. Manganese superoxide dismutase (Mn SOD) and GPx expression levels decreased slightly after myricetin treatment. In conclusion, the antioxidant capacity of myricetin was due to CAT and free-radical scavenging.