• 생약학회지
• /
• 제36권2호통권141호
• /
• pp.81-87
• /
• 2005

The effects of the DWP-04 [DDB:selenium yeast:glutathione (31.1 : 6.8 : 62.1 (w/w%)] on acetaminophen detoxification enzyme system were studied in rats. Treatment with DWP-04 was prevented againt acetaminophen-induiced hepatotoxicity in rat as evidenced by the decreased formation of lipid peroxide. Effect of DWP-04 on the activities of free radical-generating enzymes, free radical scavenging enzymes and glutathione-related enzymes as well as detoxification mechanism of DWP-04 against acetaminophen-treated was investigated in rat. Activities of cytochrome p450, cytochrome b5, aminopyrine demethylase and aniline hydroxylase as free radical-generating enzymes activities were decreased by the treatment with DWP-04 against acetaminophen treated. Although acetaminophen-induced hepatotoxicity results in the significantly decrease in the level of hepatic glutathione and activities of glutathine S-transferase, quinone reductase, glutathione reductase and ${\gamma}-glutamyl-$cysteine synthetase, these decreasing effects were markedly lowered in the DWP-04-treated rat. Therefore, it was concluded that the mechanism for the observed preventive effect of DWP-04 against the acetaminophen-induced hepatotoxicity was associated with the decreased activities in the free radical-generating enzyme system.

• 한국식품영양과학회지
• /
• 제32권6호
• /
• pp.937-941
• /
• 2003

재래종 적갓(Brassica juncea czerniak et coss)을 주재료로 담금하여 발효시킨 적갓김치(red mustard leaf kimchi, RML kimchi)의 crude anthocyanin(CA) 및 refined anthocyanin(RA) 획분들에 대한 항산화성을 규명하였다. 발효된 적갓김치는 산도 0.72(%), pH 4.6 그리고 crude anthocyanin 함량(건조물기준)은 49.4 mg/g이었다. 동결건조 적갓김치로부터 얻어진 조색소용액 (crude pigment solution)을 계통 추출분획하여 증류수 획분, methanol 획분, TFA-methanol (CA) 획분을 얻었으며, CA 획분을 계속 분획하여 정제된 5개의 정제된 RA 획분(Fr.1, Fr.2, Fr.3, Fr,4, Fr.5)을 얻었다. 이들의 항산화 활성을 linoleic acid의 autoxidation system에서 peroxide formation 억제능과 DPPH($\alpha$, $\alpha$＇-diphenyl-$\beta$-picrylhydrazyl)의 free radical 소거능에 대하여 실험하였다. 그 결과 조색소용액 분획물 중 CA 획분이 항산화능이 높았고, CA 획분으로부터 얻어진 RA 획분 중 Fr.3이 가장 높은 항산화성을 보였다. 특히 Fr.3은 적갓김치의 대표적인 anthocyanin이었고 항산화 활성은 $\alpha$-tocopherel보다는 낮았으나 그것에 접근하는 유사한 특성을 보였다. 그리고 그 활성은 지질의 과산화 억제능과 수소공여성에서 다같이 비슷한 수준의 항산화성을 보였다.

• 한방안이비인후피부과학회지
• /
• 제20권2호통권33호
• /
• pp.1-9
• /
• 2007

Objective : In this study, the ethanol extract from flowers of Lespedeza bicolor was investigated for their dermal bioactive properties related to cosmeceuticals such as depigmentation and radical scavenging effect. Results : The ethanol extract from flowers of Lespedeza bicolor showed considerable radical scavenging activity ($SC_{50}:\;10\;{\mu}g/ml$) and inhibited the production of nitric oxide (NO) in Raw 264.7 macrophages activated with the endotoxin lipopolysaccharide (LPS). Although the proliferation of B16/F10 cells was slightly decreased by the ethanol extract from flowers of Lespedeza bicolor at the concentration of $100\;{\mu}g/ml$, it did not appear necrosis. The ethanol extract from flowers of Lespedeza bicolor down-regulated melanin formation effectively. Methods : The free radical scavenging activity of Lespedeza bicolor was assayed in cell free systems using a stable free radical, 1,l-diphenyl-2-picrylhydrazyl (DPPH). Nitrite accumulated in culture medium was measured as an indicator of NO production using a Griess reaction. Cell viability was measured by MTT assay and melanin content was assessed using the method of Hosei with some modifications. Conclusions : These results suggest that the ethanol extract from flowers of Lespedeza bicolor is a potent depigmetation agent and it may be a candidate for antioxidant and anti-inflammatory agent.

• 대한본초학회지
• /
• 제23권4호
• /
• pp.121-134
• /
• 2008

Objectives: Melia toosendan(MT) has been used as a traditional Korean herbal medicine, and today it is used as a medication for colic, side aches, heartache and other disorders of liver. The aim of this study was to determine whether fractionated extracts of MT inhibit free radical generation such as DPPH radical, superoxide radical and nitric oxide, production of nitrite, an index of NO, PGE2, iNOS, COX-2 and proinflammatory cytokines in lipopolysaccharide(LPS)-treated RAW 264.7 macrophages. Methods: MT extract prepared with methanol, and then fractionated with hexane, dichloromethane, ethylacetate, n-butanol and water. Inhibitory effect of MT onto free radical generation was determined by measuring DPPH, superoxide anions and nitric oxide scavenging activities in vitro. Cytotoxic activity of extracts on RAW 264.7 cells was measured using 5-(3-caroboxymeth-oxyphenyl)-2H-tetra-zolium inner salt(MTS) assay. Intracelluar oxidation was analysed by DCF-DA assay. The nitric oxide(NO) production was measured by Griess reagent system. The levels of iNOS and COX-2 expression were confirmed by western blot. And pro inflammatory cytokines were measured by ELISA kit. Results: Our results indicated that fractionated extracts, especially dichloromethane and ethyl acetate extracts, significantly inhibited free radical generation, the LPS-induced $H_2O_2$, NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of TNF-${\alpha}$, IL-1${\beta}$ and IL-6 formation in macrophages. Conclusions: These results indicate that dichloromethane and ethyl acetate extracts of MT have potential as an agent of chronic inflammatory diseases.

• Biomolecules & Therapeutics
• /
• 제11권3호
• /
• pp.196-199
• /
• 2003

The methanol extracts from 60 plant extracts were prepared and evaluated for their antioxidative activity. Arctium lappa, Diospyros kaki, Eugenia caryophyllata, Melia azedarach and Forsythia suspensa showed the inhibitory activity against lipid peroxidation. Caesalpinia sappan, Crataegus pinnatifida, Eugenia caryophyllata, Gleditsia japonica, Osmunda japonica, Rhus javanica and Sanguisorba officinalis showed the highest inhibitory activity against DPPH radical formation. In particular, Eugenia caryophyllata demonstrated strong inhibitory activity on the lipid peroxidation and free radicals. The results suggested that selected plant extracts have a potential as natural antioxidant.

• Molecules and Cells
• /
• 제22권2호
• /
• pp.220-227
• /
• 2006

Oxidative alteration of mitochondrial cytochrome c has been linked to disease and is one of the causes of proapoptotic events. We have investigated the modification of cytochrome c by $H_2O_2$. When cytochrome c was incubated with $H_2O_2$, oligomerization of the protein increased and the formation of carbonyl derivatives and dityrosine was stimulated. Radical scavengers prevented these effects suggesting that free radicals are implicated in the $H_2O_2$-mediated oligomerization. Oligomerization was significantly inhibited by the iron chelator, deferoxamine. During incubation of deoxyribose with cytochrome c and $H_2O_2$, damage to the deoxyribose occurred in parallel with the release of iron from cytochrome c. When cytochrome c that had been exposed to $H_2O_2$ was analyzed by amino acid analysis, the tyrosine, histidine and methionine residues proved to be particularly sensitive. These results suggest that $H_2O_2$-mediated cytochrome c oligomerization is due to oxidative damage resulting from free radicals generated by a combination of the peroxidase activity of cytochrome c and the Fenton reaction of free iron released from the oxidatively-damaged protein.

• Toxicological Research
• /
• 제21권2호
• /
• pp.115-119
• /
• 2005

In the present study, we evaluated the free radical scavenging and xanthine oxidase inhibitory activities exhibited by extracts obtained from the dried stems (and leaves) of Lespedeza bicolor We also assessed its potential irritation activities with regard to cosmetic use. When the DPPH radical scavenging activities of L. bicolor were assessed at six different concentrations (0, 50, 100, 250, 500 and 1000 ${\mu}g/ml$), the concentration of L. bicolor required to inhibit DPPH radical formation by $50\%$ was found to be $164.90{\mu}g/ml$. The effects of L. bicolor on the inhibition of xanthine oxidase were determined at seven different concentrations. The $50\%$ effective concentration was found to be $282.75{\mu}g/ml$. In the skin irritation test, all animals survived for the duration of the study, and all exhibited normal gains in body weight. The control sites exhibited no response to the control procedures. No edema, erythema, or eschar formation was observed in any of the tested rabbits. In the ocular irritation study, all of the rabbit eyes remained normal. In summary, L. bicolor extracts were considered to be non-irritating to the skin and eye.

• Animal cells and systems
• /
• 제9권2호
• /
• pp.79-85
• /
• 2005

Oxidized abasic residues arise as a major class of DNA damage by a variety of agents involving free radical attack and oxidation of deoxyribose sugar components. 2-deoxyribonolactone (dL) is a C1'-oxidized abasic lesion implicated in DNA strand scission, mutagenesis, and covalent DNA-protein cross-link (DPC). We show here that mammalian cell-free extract give rise to stable DPC formation that is specifically mediated by dL residue. When a duplex DNA containing dL at the site-specific position was incubated with cell-free extracts of Po ${\beta}-proficient$ and -deficient mouse embryonic fibroblast cells, the formation of major dL-mediated DPC was dependent on the presence of DNA polymerase (Pol) ${\beta}$. Formation of dL-specific DPC was also observed with histones and FEN1 nuclease, although the reactivity in forming dL-mediated DPC was significantly higher with Pol ${\beta}$ than with histones or FEN1. DNA repair assay with a defined DPC revealed that the dL lesion once cross-linked with Pol ${\beta}$ was resistant to nucleotide excision repair activity of cell-free extract. Analysis of nucleotide excision repair utilizing a model DNA substrate containing a (6-4) photoproduct suggested that excision process for DPC was inhibited because of DNA single-strand incision at 5' of the lesion. Consequently DPC mediated by dL lesion may not be readily repaired by DNA excision repair pathway but instead function as unusual DNA damage causing a prolonged DNA strand break and trapping of the major base excision repair enzyme.

• Journal of Applied Biological Chemistry
• /
• 제63권4호
• /
• pp.327-334
• /
• 2020

산화적 스트레스는 신경퇴행성 질환 발병의 원인으로 알려져 있다. 본 연구는 대표적인 감초 종류인 Glycyrrhiza glabra, G. uralensis와 신품종 감초인 신원감(SW)의 in vitro free radical 소거능을 통한 항산화 활성과 H2O2 유도 산화적 스트레스에 대한 C6 glial cell 보호 효능을 확인하고자 하였다. In vitro assay에서 G. uralensis, G. glabra, SW 추출물은 농도유의적으로 2,2-diphenyl-1-picrylhydrazyl, ·OH, O2- radical 소거능이 증가하여 in vitro 항산화 활성을 확인하였다. 또한, SW 추출물은 G. uralensis, G. glabra 추출물에 비해 총 페놀 및 플라보노이드 함량이 가장 우수하였다. H2O2로 산화적 스트레스를 유도한 C6 glial cell에 3가지 감초 추출물을 각각 처리 시, 농도의존적으로 세포 생존율이 증가와 reactive oxygen species 소거능이 증가하여 3가지 감초 추출물의 산화적 손상에 대한 신경교세포 보호 효과를 확인하였다. 특히, SW 추출물은 G. uralensis, G. glabra 추출물에 비해 우수하게 C6 glial cell 보호 효과를 나타내었다. 또한, 3가지 감초 추출물의 신경교세포 보호 메커니즘을 확인하기 위해, 염증 관련 단백질 발현을 측정하였다. 3가지 감초 추출물은 H2O2만을 처리한 control군에 비해 inducible nitric oxide synthase 및 cyclooxygenase-2 발현 감소를 통해 염증반응 조절을 통한 신경교세포 보호 작용기전을 확인하였다. 본 연구는 G. uralensis, G. glabra, SW 등 3가지 감초 추출물이 산화적 손상이 유도된 신경교세포 보호에 유용한 소재로써의 가능성이 있는 것으로 사료된다.

• Preventive Nutrition and Food Science
• /
• 제9권2호
• /
• pp.150-155
• /
• 2004

The free radical scavenging activities and the protective effects of Rhus javanica extracts against oxidative damage induced by reactive oxygen species (ROS) were investigated. n-Hexane, ethyl acetate and water fractions were prepared from a methanol extract. DPPH radical, superoxide anion and hydroxyl radical scavenging activities were estimated. Intracellular ROS formation was quantified using fluorescent probes, 2', 7'-dichlorofluorescin diacetate (DCFH-DA) for hydroxyl radical and dihydroethidium (DHE) for superoxide anion. The oxidative DNA damage was investigated by the comet assay in HepG$_2$ cells exposed either to $H_2O$$_2$ or to menadione. The highest $IC_{50}$/ values for DPPH radical scavenging activity was found in the ethyl acetate fraction with a value of 5.38 $\mu\textrm{g}$/mL. Cells pretreated with $\geq$ 1 $\mu\textrm{g}$/mL of the ethyl acetate extract had significantly increased cell viability compared to control cells, which were not pretreated with the extract. Intracellular ROS formation and DNA damage in HepG$_2$ cells, which were pretreated with the various concentrations of Rhus javanica ethyl acetate extract and then incubated either with $H_2O$$_2$ or with menadione, reduced in a dose-dependent manner. These findings suggest that Rhus javanica might have biologically active components which have strong protective effects against ROS induced oxidative damages to the biomolecules, such as cell membranes and DNA.