• 제목/요약/키워드: Radical mechanism

검색결과 500건 처리시간 0.026초

항암성 백금화합물의 신장독성에 관한 연구 (Studies on the Mechanism of Nephrotoxicity Caused by Antitumor Platinum Complex)

  • 최병기;박영숙;정세영
    • Environmental Analysis Health and Toxicology
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    • 제8권3_4호
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    • pp.23-32
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    • 1993
  • This study was designed to elucidate the mechanism of nephrotoxicity caused by antitumor agent tetraphosphine platinum (II) complex (RC-1), which was synthesized as a tetraphosphine Pt (II) derivatives recently. Rats treated with RC-1 (20mg/kg/day) showed the increase of BUN value and malondialdehyde contents in kidney homogenate, compared to the control and which means the lipid peroxidation was a main cause of nephrotoxicity. In order to investigate the cytotoxic mechanism of RC-1, we also tested and revealed the generation of oxygen free radicals derived from neutrophil stimulated by RC-1 and interaction of the oxygen free radicals with the erythrocyte membrane. From the above results, we suggest that nephrotoxicity of general platinum (II) antitumor compounds as well as RC-1 were inhibited by radical scavengers.

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단삼 메탄올 추출물의 항혈전 및 항산화 효과 (Effects of Methanolic Extract from Salvia miltiorrhiza Bunge on in vitro Antithrombotic and Antioxidative Activities)

  • 양선아;임남경;이인선
    • 한국식품과학회지
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    • 제39권1호
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    • pp.83-87
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    • 2007
  • 단삼 메탄올 추출물의 항혈전 및 항산화 효과를 확인하기 위하여 혈소판의 응고 억제효과, 혈장응고시간의 연장, 혈전용해 활성으로 항혈전 효과를 고찰하였으며 DPPH radical 소거능을 측정하여 항산화 효과를 검토하였다. 그 결과, 단삼의 메탄올 추출물은 항혈전과 항산화에 효과가 있는 것으로 나타났다. 이 추출물은 혈소판응고 억제, 혈액응고시간 연장 및 혈전용해 활성에 모두 효과가 좋은 것으로 나타났으며, 폴리페놀 함량이 높고 DPPH radical 소거능도 매우 좋았다. 이로서 단삼의 높은 DPPH radical 소거능이 항혈전 효과에 영향을 미치는 것으로 사료되며, 정확한 효과 및 혈소판의 기능을 조절하는 기전에 대한 연구는 이 결과들을 바탕으로 현재 진행 중에 있다.

Radical Intermediate Generation and Cell Cycle Arrest by an Aqueous Extract of Thunbergia Laurifolia Linn. in Human Breast Cancer Cells

  • Jetawattana, Suwimol;Boonsirichai, Kanokporn;Charoen, Savapong;Martin, Sean M
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권10호
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    • pp.4357-4361
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    • 2015
  • Thunbergia Laurifolia Linn. (TL) is one of the most familiar plants in Thai traditional medicine that is used to treat various conditions, including cancer. However, the antitumor activity of TL or its constituents has never been reported at the molecular level to support the folklore claim. The present study was designed to investigate the antitumor effect of an aqueous extract of TL in human breast cancer cells and the possible mechanism(s) of action. An aqueous crude extract was prepared from dried leaves of TL. Folin-Ciocalteu colorimetric assays were used to determine the total phenolic content. Antiproliferative and cell cycle effects were evaluated in human breast adenocarcinoma MCF-7 cells by MTT reduction assay, cell growth inhibition, clonogenic cell survival, and flow cytometric analysis. Free radical generation by the extracts was detected using electron paramagnetic resonance spectroscopy. The exposure of human breast adenocarcinoma MCF-7 cells to a TL aqueous extract resulted in decreases in cell growth, clonogenic cell survival, and cell viability in a concentration-dependent manner with an $IC_{50}$ value of $843{\mu}g/ml$. Treatments with extract for 24h at $250{\mu}g/ml$ or higher induced cell cycle arrest as indicated by a significant increase of cell population in the G1 phase and a significant decrease in the S phase of the cell cycle. The capability of the aqueous extract to generate radical intermediates was observed at both high pH and near-neutral pH conditions. The findings suggest the antitumor bioactivities of TL against selected breast cancer cells may be due to induction of a G1 cell cycle arrest. Cytotoxicity and cell cycle perturbation that are associated with a high concentration of the extract could be in part explained by the total phenolic contents in the extract and the capacity to generate radical intermediates to modulate cellular proliferative signals.

연근(蓮根)의 신경 보호 효과 및 기전연구 (The Mechanism of Lotus Root Extract (LRE) as Neuro-Protective Effect in Alzheimer Disease (AD))

  • 홍승철;이가굉;김상헌;이진희;구병수
    • 동의신경정신과학회지
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    • 제24권3호
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    • pp.309-320
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    • 2013
  • Objectives : There is a possibility LRE as remedy in Alzheimer disease (AD), but it's nerve protection effect and mechanism have to be elucidate. In this research, we applied LRE on $A{\beta}_{25-35}$ pre-treated SH-SY5Y cells, to find out the nerve protection effect and mechanism in AD cell model. Methods : We tried to confirm that effect by experimenting with 20, 50, and $100{\mu}g/ml$ concentration of LRE as a medicine. Next experiment, we assessed damage effect which induced $A{\beta}_{25-35}$, known to cause AD, on SH-SY5Y cell. In addition, cellular viability test is executed under $H_2O_2$ treatment condition in a SH-SY5Y cell. Results : 1. In $A{\beta}_{25-35}$ treated SH-SY5Y cell, LRE exhibited an anti-phosphorylation effect about tau protein, JNK, and IKB. 2. LRE prevent nerve cell apoptosis, which indued $A{\beta}_{25-35}$ and oxidative stress, modify JNK engaged synaptic structure and $NF{\kappa}B$ induced p75-neurotrophin receptor polymorphism. Conclusions : We found that LRE prevented oxidative stress-induced cellular destruction, for example, increased SOD activity of $A{\beta}_{25-35}$ treated SH-SY5Y cell and reduced toxicity of oxygen free radical. Consequently, the ingredients of LRE have a role as a catalyzer for $A{\beta}_{25-35}$ clearance and as scavenger for active oxygen free radical.

전기화학적 공정에 의한 클로레이트의 생성메커니즘 (Formation Mechanism of Chlorate ($ClO_3\;^-$) by Electrochemical Process)

  • 백고운;정연정;강준원;오병수
    • 대한환경공학회지
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    • 제31권8호
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    • pp.627-634
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    • 2009
  • 본 연구는 염화 이온 ($Cl^-$)을 전해질로 이용하는 전기화학적 공정에서 생성되는 염소산화부산물인 클로레이트 ($ClO_3\;^-$, 염소산염)의 생성 메커니즘을 알아보기 위해 수행되었다. 우선, pH 및 초기농도에 따른 생성 특성을 살펴보았으며, 유리염소 생성과의 관련성 및 오존, OH 라디칼 등의 혼합산화제의 영향을 간접 평가하여 클로레이트의 생성 메커니즘을 구체화하였다. 그 결과, 클로레이트의 생성은 유리염소 (HOCl/$OCl^-$)의 전기화학적 반응을 주된 반응으로 하며, 염화 이온의 직접 양극산화 반응 및 OH 라디칼에 의한 경로가 있음을 확인하였다. 이어서 생성된 클로레이트가 퍼클로레이트로 산화되는 반응도 볼 수 있었다. 또한, 전극 간격에 따른 생성 농도를 유리염소 생성과 함께 평가하여, 유리염소 생성 효율은 극대화 시키되 클로레이트의 발생을 최소화 할 수 있는 최적조건을 찾는 방안을 제시하였다.

노화(老化)의 연구동향(硏究動向)에 관한 고찰(考察) (The Study on Aging Process Research)

  • 이홍민;서정철;김용석
    • Journal of Acupuncture Research
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    • 제18권1호
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    • pp.146-156
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    • 2001
  • Objectrve : To research the trends of the study related to aging process, and to establish the direction of the study on aging process. Method : We reviewed the journal and essay about the aging process which are published as well in Korea as in foreign country. Results : 1. The study on the Oriental Medicine field can be classfied with the fourth. first, the study of single herb medication's effect on the aging process. second, the study of multiple herb medication's effect on the aging process. third, the study of herb-acupuncture solution's effect on the aging process. fourth, journal review. We find the fact that the study on the Oriental Medicine is concerned with pathology of deficiency syndrome of the kidneys, retention of phlegm and fluid, blood stasis. 2. On the Western Medicine field, mechanism and pathology of aging pracess primarily has been studied. The mechanism of aging process is classified with 'Wear and tear theory' and 'Genome-based theory'. Among the mechanism of aging process, 'Free radical theory' is the most important. Additionally 'Senescence-Accelerated Mouse' has been studied. 3. We review the journal published in foreign country and its subject was the following: first, moxibustion combined with acu-area skin allograft therapy for the aging was effective, second, the traditional chinese medicine bu-zhong-yi-qi-tang in mice have anti-aging effect. third, the overview Preventive geriatrics of Traditional chinese medicine. 4. We researched anti-aging effect study in the journal of the Korean Acupuncture and Moxibustion, and we found a few journal of Herb-acupuncture solution's anti-aging effect. Hereafter, it is necessory that we will study about relationship between acupuncture-moxibustion therpy and anti-aging effect using Senescence-Accelerated Mouse.

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내독소에 의한 백서의 급성 폐손상에서 Hydroxyl Radical의 병인론적 역할에 관한 연구 (The Role of Hydroxyl Radical in the Pathogenetic Mechanism of Endotoxin-Induced Acute Lung Injury in Rats)

  • 심영수;유철규;김영환;한성구;김건열;한용철
    • Tuberculosis and Respiratory Diseases
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    • 제39권2호
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    • pp.120-130
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    • 1992
  • 연구배경 : 급성 폐손상의 기전에 관한 연구는 많이 진행되어 있으나 아직 확실한 결론을 내리기에는 미흡한 실정이다. 최근에 산소기의 병인론적 역할에 관한 관심이 고조되고 있으나 이것도 아직 확실히 규명되지 못한 실정이고 내독소에 의한 백서의 급성 폐손상에 관해서는 경험이 일천한 상태이다. 이에 저자들은 백서에서 내독소투여 후 시간경과에 따른 폐포내 호중구 침윤과 폐포-모세혈관 투과성의 변화를 관찰하고 hydroxyl radical 탐식제인 DMTU와 hydroxyl radical 형성에 중요한 역할을 하는 철분제거제인 DFX 전처치가 이에 미치는 영향을 관찰하여 hydroxyl radical이 내독소에 의한 백서의 급성 폐손상에서 호중구의 이동과 폐포-모세혈관 투과성의 증가에 마치는 영향을 평가하고자 본 연구를 시행하였다. 방법 : 50마리의 백서를 대조군 (n=5, 6hrs; n=5, 24hrs), 내독소 투여군 (n=10, 6hrs; n=10 24hrs), DMTU 전처치군 (n=10, 6hrs) 과 DFX 전처치군 (n=10, 6hrs) 으로 나누어 희생하기 30분전에 $^{125}I$을 붙인 bovine serum albwnin을 꼬리 정맥에 주사하였다. 내독소를 투여하고 6시간과 24시간이 경과한 후 백서를 희생시켜서 폐조직과 말초혈액 1 ml의 방사능을 측정하여 이 둘의 비를 폐포-모세혈관 투과성의 지표로 사용하였다. 다른 52마리의 백서를 위와 같이 4개의 군으로 나누어 [대조군 (n=5, 6hrs; n=5, 24hrs), 내독소투여군 (n=7, 6hrs; n=8, 24hrs), DMTU 전처치군 (n=6, 6hrs; n=9, 24hrs)과 DFX 전처치군 (n=5, 6hrs; n=7, 24hrs)] 내독소를 투여하고 6시간과 24시간이 경과한 후 희생시켜 말초혈액과 기관지폐포세척액의 구성세포와 폐의 병리조직학적 소견을 관찰하였다. 결과 : 내독소를 투여하고 6시간이 경과한 후 폐포-모세혈관 투과성이 증가되었다가 24시간이 경과한 후 정상대조군 수준으로 회복되는 양상을 보였는데 6시간만에 DMTU와 DFX 전처치로 유의하게 완화되었다. 폐조직으로의 호중구 침윤은 내독소를 투여하고 24시간이 경과한 후 관찰되었는데 이는 DMTU와 DFX 전처치로 완화되지 않았다. 결론 : 이상의 결과로 내독소에 의한 백서의 급성 폐손상에서 hydroxyl radical은 호중구의 이동에는 관여하지 않을 것으로 생각되며 주로 폐포-모세혈관 투과성 증가에 관여할 것으로 생각된다.

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Effects of Flavonoids of Ginseng Leaves on Erythrocyte Membranes against Single Oxygen Caused Damage

  • Park, Soo-Nam;Choi, Sang-Won;Boo, Yong-Chool;Kim, Chang-Kew;Lee, Tae-Young
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1990년도 Proceedings of International Symposium on Korean Ginseng, 1990, Seoul, Korea
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    • pp.49-57
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    • 1990
  • It has been well known that extended exposure to reactive oxygens causes severe damage to susceptible biomolecules. In this study, the effects of flavonoids including trifling and kaempferol from Ginseng leaves on single oxygen induced photohemolysis of erythrocytes and free radical scavenging activities were investigated . Each flavonoid aglycone (5-50UM) such as kaempferol, quercetin or baicalein exhibited a high protective effect against the photohemolysis. They protected the cells by scavenging 102 and free radicals. Although the free radical scavenging activities of the flavonoid glycosides were not much lower than those of their corresponding aglycones, their insolubility into lipid bilayers of membrane made them less effective in preventing the photohemolysis induced by 1O2. The 102 and free radical scavenging activities of flavonoids were estimated by the decomposition of the flavonoid by 1O2 and the bleaching of free radicals by the flavonoid, respectively. The solubilization of the flavonoid into micelle or erythrocytes was deduced from spectrophotometric and microscopic observations. The cooperation of L-ascorbic acid and a flavonoid, and a possible involvement of lipoxygenase or cyclooxygenase in the photohemolysis mechanism were discussed. Keywords Panax ginseng C.A Meyer, ginseng leaves, flavonoids, singe1 oxygen, Photohemolysis.

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유산균의 활성산소 소거 및 면역증강효과 (Effect of Lactobacilli on Reactive Oxygen Scavenging and Immune Stimulation)

  • 이호;양승각;박수남;전도용
    • KSBB Journal
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    • 제7권4호
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    • pp.290-295
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    • 1992
  • 여러 가지 생리랴 활성기능을 가지고 있다고 알려진 유산균에 대해 활성산소 소거효과 및 면역 증강 효과 를 검토하여 보았다. 유산균 배양액 및 파쇄액의 활성산소 소거효과를 각각 다른 검색방법에 의해 살펴 본 결과, 유산균 배 양액 및 Mn-complex는 XOD assay와 paraquat에 대한 반응에서 활성 산소 소거 효과가 뛰어나 superoxide anion radical 소거와 관련이 있는 것으로 나타났고, 배양액 중에서 $Mn^{2+}$와 결합하는 성분은 누로 peptide나 amino acid인 것으로 추정된다. 한편 cell free extract는 광용혈 시험에서 좋은 효과를 나타내어 singlet oxygen 소거와 관련이 있는 것으로 생각되며, 또한 cell free extract 는 T세포를 자극하여 생성된 액성인자에 의해 B세포에 항체 생성능을 증가시키는 것으로 나타났다.

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일중항 산소($^1$O$_2$)에 의한 적헐구막 손상에 미치는 인삼잎 플라보노이드의 영향 (Effects of Flavonoids of Ginseng Leaves on Erythrocyte Membranes against Singlet Oxygen Caused Damage)

  • Soo-Nam Park;San
    • Journal of Ginseng Research
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    • 제14권2호
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    • pp.191-199
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    • 1990
  • It has been well known that extended exposure to reactive oxygens causes severe damage to susceptible biomolecules. In this study, the effects of flavonoids including trifolin and kaempferol from Ginseng leaves on singlet oxygen induced photohemolysis of erythrocytes and free radical scavenging activities were investigated. Each flavonoid aglycone (5-50$\mu$M) such as kaempferol, quercetin or baicalein exhibited a high protective effect against the photohemolysis. They protected the cells by scavenging $^1O_2$ and free radicals Although the free radical scavenging activities of the flavonoid glycosides were not much lower than those of their corresponding aglycones, their insolubility into lipid bilayers of membrane made them less effective in preventing the photohemolysis induced by $^1O_2$. The $^1O_2$ and free radical scavenging activities of flavonoids were estimated by the decomposition of the flavonoid by $^1O_2$ and the bleaching of free radicals by the flavonoid, respectively. The solubilization of the flavonoid into micells or erythrocytes was deduced from spectrophotometric and microscopic observations. The cooperation of L-ascorbic acid and a flavonoid, and a possible involvement of lipoxygenase or cyclooxygenase in the photohemolysis mechanism were discussed.

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