• Title/Summary/Keyword: reactive oxygen species

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Astaxanthin Biosynthesis Enhanced by Reactive Oxygen Species in the Green Alga Haematococcus pluvialis

  • Kobayashi, Makio
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.6
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    • pp.322-330
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    • 2003
  • The unicellular green alga Haematococcus pluvialis has recently attracted great inter-est due to its large amounts of ketocarotenoid astaxanthin, 3,3'-dihydroxy-${\beta}$,${\beta}$-carotene-4,4'-dione, widely used commercially as a source of pigment for aquaculture. In the life cycle of H. pluvialis, astaxanthin biosynthesis is associated with a remarkable morphological change from green motile vegetative cells into red immotile cyst cells as the resting stage. In recent years we have studied this morphological process from two aspects: defining conditions governing astaxanthin biosynthesis and questioning the possible function of astaxanthin in protecting algal cells against environmental stress. Astaxanthin accumulation in cysts was induced by a variety of environmental conditions of oxidative stress caused by reactive oxygen species, intense light, drought, high salinity, and high temperature. In the adaptation to stress, abscisic acid induced by reactive oxygen species, would function as a hormone in algal morphogenesis from veget ative to cyst cells. Furthermore, measurements of both in vitro and in vivo antioxidative activities of astaxanthin clearly demonstrated that tolerance to excessive reactive oxygen species is greater in astaxanthin-rich cysts than in astaxanthin-poor cysts or astaxanthin-less vegetative cells. Therefore, reactive oxygen species are involved in the regulation of both algal morph O-genesis and carotenogenesis, and the accumulated astaxanthin in cysts can function as a protective agent against oxidative stress damage. In this study, the physiological roles of astaxanthin in stress response and cell protection are reviewed.

Prostaglandin $F_2{\alpha}$ Controls Reactive Oxygen Species in Bovine Corpus Luteum

  • Lee, Seunghyung;Yang, Boo-Keun;Park, Choon-Keun
    • Reproductive and Developmental Biology
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    • v.39 no.1
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    • pp.1-6
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    • 2015
  • Luteolysis is a cyclical regression of the corpus luteum in many non-primate mammalian species. Prostaglandin $F_2{\alpha}$($PGF_2{\alpha}$) from the uterus and ovary induces functional and structural luteolysis in bovine. The action of $PGF_2{\alpha}$ is mediated by $PGF_2{\alpha}$ receptor located on the luteal steroidogenic and endothelial cell membranes. $PGF_2{\alpha}$ plays an important role in regulating nitric oxide production in endothelial cells of the bovine corpus luteum. Nitric oxide production and nitric oxide synthase activity are stimulated and induced by $PGF_2{\alpha}$ in luteal endothelial cells. Moreover, the reactive oxygen species inhibits progesterone secretion in bovine luteal cells and induces apoptosis. Thus, the interaction between $PGF_2{\alpha}$ and reactive oxygen species provides important aspects in physiology of the corpus luteum forfunctional and structural luteolysis.

Formation of Reactive Oxygen Species and Cr(V) Entities in Chromium(VI) Exposed A549 Cells (크롬 6가 투여 후 A549 세포에서의 Reactive Oxygen Species와 크롬 5가의 발생)

  • 박형숙
    • Environmental Analysis Health and Toxicology
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    • v.11 no.1_2
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    • pp.49-57
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    • 1996
  • The production of reactive oxygen species on addition of hexavalent chromium (potassium dichromate, $K_2Cr_2O_7$ ) to lung cells in culture was studied using flow cytometer analysis. A Coulter Epics Profile flow cytometer was used to detect the formation of reactive oxygen species after $K_2Cr_2O_7$ was added to A549 cells grown to confluence. The cells were loaded with the dye, 2',7'-dichlorofluorescein diacetate, after which cellular esterases removed the acetate groups and the dye was trapped intracellularly. Reactive oxygen species oxidized the dye, with resultant fluorescence. Increased doses of Cr(VI) caused increasing fluorescence (10-fold higher than background at 200 gM). Addition of Cr(III) compounds, as the picolinate or chloride, caused no increased fluorescence. Electron paramagnetic resonance (EPR) spectroscopic studies indicated that three (as yet unidentified) spectral "signals" of the free radical type were formed on addition of 20, 50, 100 and 200 gM Cr(VI) to the A549 cells in suspension. Two other EPR 'signals" with the characteristics of Cr(V) entities were seen at field values lower than the standard free radical value. radical value.

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다양한 기체를 사용한 대기압 플라즈마 젯에 대한 세포 내 활성 산소종의 영향 연구

  • Jo, Hye-Min;Kim, Seon-Ja;Jeong, Tae-Hun;Im, Seon-Hui
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.542-542
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    • 2013
  • 저온 플라즈마를 발생시키는 대기압 마이크로-플라즈마 젯(Micro-plasma jet)을 이용하여 플라즈마와 세포와의 상호작용에 대한 연구를 진행하였다. 세포의 대사과정에서 생성되는 활성산소 종(Reactive Oxygen Species, ROS)은 세포에 산화 스트레스를 유발시킨다. 이러한 스트레스는 세포 예정사(programmed cell death)의 원인이 된다. 플라즈마 형성 기체로 헬륨, 아르곤, 질소를 사용하여 각각의 기체에 따른 세포의 형태 변화 및 세포 내 활성 산소 종의 영향을 분석하였다. 실험에 사용된 세포는 인체의 폐암 세포[Human lung cancer cell, A549]이며 플라즈마 처리 후 Intracellular ROS assay를 통하여 플라즈마에서 발생되는 활성 산소 종(Reactive Oxygen Species, ROS)이 세포 내에 들어가 활성 산소 종을 증가시키는 것을 확인하였다. 이때, 플라즈마에서 발생되는 활성 산소 종(Reactive Oxygen Species, ROS)들은 광 방출 스펙트럼(Optical Emission Spectroscopy)로 분석하였고, 기체별로 비교하여 보았다. 또한, 이 때 발생되는 플라즈마의 전류-전압 특성에 따른 optical intensity를 비교하였다.

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Identification of Atherosclerosis Related Gene Expression Profiles by Treatment of Benzo(a)pyrene in Human Umbilical Vein Endothelial Cells

  • Lee, Sun-Hee;Lee, Seung-Eun;Ahn, Hyun-Jong;Park, Cheung-Seog;Cho, Jeong-Je;Park, Yong-Seek
    • Molecular & Cellular Toxicology
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    • v.5 no.2
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    • pp.113-119
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    • 2009
  • Benzo(a)pyrene (BaP) is a persistent environmental contaminant and is present in tobacco smoke. BaP is considered a major contributor of cardiovascular disease. While the activation of endothelial cells by stimuli including tobacco smoke and air pollution contributes importantly to cardiovascular disease, the nature of BaP's mechanism is unclear. In this study, gene expression profiles were investigated in BaPtreated human umbilical vein endothelial cells (HUVECs). Various atherosclerosis related genes could be up- and down-regulated more than 2-fold by BaP, and mRNA levels of atherosclerosis related genes encoding apolipoproteinC III, TLR 2, ICAM 1 and exportin 4 were significantly increased by BaP. Our data suggest that BaP-mediated changes in gene expression contribute to the progression of cardiovascular disease.

The Effect of Nitroprusside on the Sperm Motility, Viability, and Reactive Oxygen Species Generation (Nitroprusside가 인간정자의 생존력, 운동성, Reactive Oxygen Species 발생에 미치는 영향)

  • Min, Bu-Kie;Lee, Hee-Min;Kim, Ki-Seok;Lee, Hee-Sup;Kim, Heung-Gon;Hong, Gi-Youn;Lee, Bong-Ju
    • Clinical and Experimental Reproductive Medicine
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    • v.23 no.3
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    • pp.351-355
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    • 1996
  • Objective: To analyze the direct effect of nitre oxide, generated from sodium nitroprusside, on sperm motility and reactive oxygen species. Design: Human sperm samples were treated to allow swim-up and washing. And the samples were devided into four aliquots. Each aliquot was incubated with either concentration at 0, 100nM, $10{\mu}M$, 1mM of nitroprusside. Intervention: Samples were measured chemiluminosence for reactive oxygen species of each aliquot with concentrations at 0, 100nM, $10{\mu}M$, 1mM of nitroprusside at allowing swim-up and washing of sperm. Main Outcome Measures: Percent motion parameters and viability were asse-ssed at 0, 3, 6, 12, 24 hours incubation. Results: The percent viablity was lower slightly in control group (50.2%) than that in sperm treated with 100nM of nitroprusside(57.5%) at 24 hours after incubation, while was reduced significantly in sperm with concentra-tion of $10{\mu}M(42.1%)$ and 1mM(21.3%)of nitroprusside at 6 hours after incubation. And the sperm treated with 1mM of nitroprusside was immotile totally at 6 hours after incubation. The straight line$(35.3{\pm}5.6%)$, the rapid forward$(37.2{\pm}6.4%)$ and the weak curvilinear velocity$(9.6{\pm}2.4%)$were more favorable comparing with those ($32.4{\pm}4.2%$, $30.0{\pm}7.8%$ and $18.0{\pm}4.6%$ respectively) in control group at 3 hours after incubation, but reduced significantly in sperm treated with $10{\mu}M$ and 1mM of nitroprusside. The levels of reactive oxygen species in control(700 c.p.m.) is lower significantly than that in each experimental groups of sperm treated with nitroprusside. And the levels of reactive oxygen species were 2200 c.p.m. in 100nM, 6200c.p.m. in $1{\mu}M$ and 12800c.p.m. in 1mM respectively. Conclusion: These results suggested that the concentration of 100nM of nitroprusside on sperm is beneficial to the maintanance of viablity and motile velocity, but detriment in high concentration of $10{\mu}M$ or 1mM of nitroprusside.

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Formation of Cross-Linked Products of The Reaction Center D1 Protein in Photosystem II under Light Stress

  • Uchida, Suguru;Kato, Yoji;Yamamoto, Yasusi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.382-384
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    • 2002
  • When illuminated with strong visible light, the reaction center Dl protein of photo system II is photodamage and degraded. Reactive oxygen species and endogenous cationic radicals generated by photochemical reactions are the cause of the damage to the Dl protein. Recently we found that the photodamaged Dl protein cross-links with the surrounding polypeptides such as D2 and CP43 in photosystem II. As the cross-linking reaction is dependent on the presence of oxygen, reactive oxygen species are suggested to be involved. Among the reactive oxygen species examined, ? OH was most effective in the formation of the cross-linked products. These results indicate that the cross-linking is mostly due to ? OH generated at photosystem II. The cross-linking site of the Dl protein is not known. As several tyrosine residues exist at the D­E loop of the Dl protein, there is a possibility that di-Tyr is formed between the D­E loop of the Dl protein and surrounding polypeptides during the strong illumination. Therefore, we examined the formation of di-Tyr using the monoclonal antibody against di-Tyr under excess illumination of the photosystem II membranes. The results obtained here suggest that no di-Tyr is formed during the excess illumination of photosystem II.

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Protective Effect of Fisetin (3,7,3',4'-Tetrahydroxyflavone) against γ-Irradiation-Induced Oxidative Stress and Cell Damage

  • Piao, Mei Jing;Kim, Ki Cheon;Chae, Sungwook;Keum, Young Sam;Kim, Hye Sun;Hyun, Jin Won
    • Biomolecules & Therapeutics
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    • v.21 no.3
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    • pp.210-215
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    • 2013
  • Ionizing radiation can induce cellular oxidative stress through the generation of reactive oxygen species, resulting in cell damage and cell death. The aim of this study was to determine whether the antioxidant effects of the flavonoid fisetin (3,7,3',4'-tetrahydroxyflavone) included the radioprotection of cells exposed to ${\gamma}$-irradiation. Fisetin reduced the levels of intracellular reactive oxygen species generated by ${\gamma}$-irradiation and thereby protected cells against ${\gamma}$-irradiation-induced membrane lipid peroxidation, DNA damage, and protein carbonylation. In addition, fisetin maintained the viability of irradiated cells by partially inhibiting ${\gamma}$-irradiation-induced apoptosis and restoring mitochondrial membrane potential. These effects suggest that the cellular protective effects of fisetin against ${\gamma}$-irradiation are mainly due to its inhibition of reactive oxygen species generation.

Antioxidant Activity and Tolerance to Reactive Oxygen Species of Lactobacillus spp. (Lactobacill spp. 의 황산화 효과 및 활성산소에 대한 내성)

  • Kim, H.S.;Jeong, S.G.;Chae, H.S.;Ham, J.S.;Ahn, C.N.;Lee, J.M.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.1007-1012
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    • 2004
  • The four Lactobacillus spp. were investigated for their antioxidant properties, including antioxidant activity, tolerance to reactive oxygen species, hydroxy radical scavenging activity and ferrous iron che1ating activity. Also, activities of superoxide dismutase and glutathione peroxidase were investigated. From the results of this work, the intact cell and cell lysate of L. casei KCTC 3260 were exhibited highest antioxidant activity. L. casei KCTC 3260 also showed strong tolerance to reactive oxygen species. This strain showed highest glutathione peroxidase activity among the tested strains.