• 동의생리병리학회지
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• 제21권1호
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• pp.165-170
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• 2007

Pyungwi-san(PWS) have been using as a basic prescription of digestive disorder in Korean traditional medicine. This study was performed to examine the in vitro antioxidant activity of the extract using different antioxidant tests including by 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging, superoxide anion radical scavenging, metal chelating hydrogen peroxide scavenging, lipid peroxydation protective effect and scavenging effect of nitric oxide and peroxynitrite. Herbal-acupuncture solution of PWS(PWS-HS) exhibited a concentration-dependent inhibition of DPPH radical adduct formation and it showed dose-dependent free radical scavenging activity onto superoxide anions. In addition, the result of metal chelating hydrogen peroxide scavenging and ammonium thiocyanate experiments showed that PWS-HS was an active scavenger of hydroxyl radicals. Furthermore, it was also found to be effective in scavenging nitric oxide and peroxynitrite, well-known cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA.

• 환경생물
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• 제20권1호
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• pp.35-39
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• 2002

The significance of cell ploidy and repair ability for the radioprotective efficiency of cysteamine was studied in DNA repair - proficient and repair - deficient yeast cells irradiated $^{60}C0\;\gamma-rays.$ Results have been obtained for the cell survival of two groups of yeasts-diplont and haplont cells, both in haploid and diploid states. For diploid Saccharomyces cerevisiae yeast cells, the correlation between the radio-protective action of cysteamine and the cell repair capacity was demonstrated. Such a correlation was not clearly expressed for haploid yeast cells. In addition, evidence was obtained indicating that the degree of the radioprotective action was independent of the number of chromosome sets in haplont yeast Pichia guilliermondii cells and in some radiosensitive mutants defective in the diploid-specific recovery. It is concluded on this basis that the radioprotective action may involve the cellular recovery process, which may be mediated by a recombination-like mechanism, for which the diploid state is required. The results obtained clearly show that the radioprotective effect was dependent on DNA repair status and indicate that the mechanism of the radioprotective action may be realized on the level of primary radiation damage production as well as on the level of postradiation recovery from potentially lethal radiation damage.

• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.271-278
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• 2001

Oxidative stress and methylglyoxal (MG), a reactive dicarbonyl metabolites produced by enzymatic and non-enzymatic reaction of normal metabolism, induced aldose reductase (AR) expression in rat aortic smooth muscle cells (SMC). AR expression was induced in a time-dependent manner and reached at a maximum of 4.5-fold in 12 h of MG treatment. This effect of MG was completely abolished by cyclohemide and actinomycin D treatment suggesting AR was synthesized by de novo pathway. Pretreatment of the SMC with N-acetyl-L-cysteine significantly down-regulated the MG-induced AR mRNA. Furthermore, DL-Buthionine-(S,R)-sulfoximine, a reagent which depletes intracellular glutathione levels, increased the levels of MG-induced AR mRNA. These results indicated that MG induces AR mRNA by increasing the intracellular peroxide levels. Aminoguanidine, a scanvenger of dicarbonyl, significantly down-regulated the MG-induced AR mRNA. In addition, the inhibition of AR activities with statil, an AR inhibitor, enhanced the cytotoxic effect of MG on SMC under normal glucose, suggesting a protective role of AR against MG-induced cell damages. These results imply that the induction of AR by MG may contribute to an important cellular detoxification of reactive aldehyde compounds generated under oxidative stress in extrahepatic tissues.

• Molecular & Cellular Toxicology
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• 제4권2호
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• pp.157-163
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• 2008

Formation of ${\beta}$-amyloid $(A{\beta})$ fibrils has been identified as one of the major characteristics of Alzheimer's disease (AD). Inhibition of $A{\beta}$ fibril formation in the CNS would be attractive therapeutic targets for the treatment of AD. Several small compounds that inhibit amyloid formation or amyloid neurotoxicity in vitro have been known. Citrate has surfactant function effect because of its molecular structure having high anionic charge density, in addition to the well-known antibacterial and antioxidant properties. Therefore, we hypothesized that citrate might have the inhibitory effect against $A{\beta}$ fibril formation in vitro and have the protective effect against $A{\beta}$-induced neurotoxicity in PC12 cells. We examined the effect of citrate against the formation of $A{\beta}$ fibrils by measuring the intensity of fluorescence in thioflavin-T (Th-T) assay of between $A{\beta}_{25-35}$ groups treated with citrate and the control with $A{\beta}_{25-35}$ alone. The neuroprotective effect of citrate against $A{\beta}$-induced toxicity in PC12 cells was investigated using the WST-1 assay. Fluorescence spectroscopy showed that citrate inhibited dose-dependently the formation of $A{\beta}$ fibrils from ${\beta}$-amyloid peptides. The inhibition percentages of $A{\beta}$ fibril formation by citrate (1, 2.5, and 5 mM) were 31%, 60%, and 68% at 7 days, respectively in thioflavin-T (Th-T) assay. WST-1 assay revealed that the toxic effect of $A{\beta}_{25-35}$ was reduced, in a dose-dependent manner to citrate. The percentages of neuroprotection by citrate (1, 2.5, and 5 mM) against $A{\beta}-induced$ toxicity were 19%, 31 %, and 34%, respectively. We report that citrate inhibits the formation of $A{\beta}$ fibrils in vitro and has neuroprotective effect against $A{\beta}$-induced toxicity in PC12 cells. Neuroprotective effects of citrate against $A{\beta}$ might be, to some extent, attributable to its inhibition of $A{\beta}$ fibril formation. Although the mechanism of anti-amyloidogenic activity is not clear, the possible mechanism is that citrate might have two effects, salting-in and surfactant effects. These results suggest that citrate could be of potential therapeutic value in Alzheimer's disease.

• 한국미생물·생명공학회지
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• 제41권3호
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• pp.284-291
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• 2013

본 연구에서는 화장품 원료로서 삼지구엽초의 응용가능성을 확인하기 위해 항균 효과와 항산화 효과를 확인하였다. 피부상재균에 대한 disc diffusion assay에서 높은 항균 효과를 나타낸 분획-균에 대해 최소저해농도를 측정하였다. Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Propionibacterium acnes (P. acnes)에 대한 에틸아세테이트 분획의 항균 활성과, S. aureus에 대한 50% 에탄올 분획의 항균 활성은 대표적인 방부제인 methyl paraben보다 우수한 것으로 확인되었다. DPPH (1,1-diphenyl-2-picrylhydrazyl)를 이용한 라디칼 소거 활성에서는 삼지구엽초의 세 분획 모두 대표적 항산화제인 (+)-${\alpha}$-토코페롤보다 낮은 것으로 나타났다. $Fe^{3+}-EDTA/H_2O_2$ 계를 이용해 다양한 ROS에 대한 총 항산화 활성($OSC_{50}$)을 실험한 결과, 50% 에탄올 추출물($OSC_{50}=2.46{\pm}0.06{\mu}g/ml$)과 아글리콘 분획($OSC_{50}=1.45{\pm}0.02{\mu}g/ml$)은 비교 물질인 L-ascorbic acid($OSC_{50}=1.50{\pm}0.85{\mu}g/ml$)과 유사한 높은 활성을 보여주었다. 광증감 반응을 이용한 세포 보호 효과(${\tau}_{50}$) 실험에서 50% 에탄올 추출물(${\tau}_{50}=37.0{\pm}0.3$ min)은 비교 물질인 (+)-${\alpha}$-토코페롤(${\tau}_{50}=38.0{\pm}1.8$ min)과 유사한 값을 보여주었다. 특히 아글리콘 분획의 ${\tau}_{50}$은 $165.9{\pm}7.2$ min으로 비교 물질인 (+)-${\alpha}$-토코페롤에 비해 4배가 넘는 높은 세포 보호 효과를 나타내었다. 이러한 결과들을 종합해보았을 때, 삼지구엽초 추출물은 항균 또는 항산화 활성을 갖는 화장품 원료로서 응용가능성이 높은 것으로 확인하였다.

• 생명과학회지
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• 제31권2호
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• pp.126-136
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• 2021

산화적 스트레스에 의한 망막 색소상피 세포의 손상 및 퇴화는 시력 소실을 포함한 다양한 망막질환의 원인으로 알려져 있다. 본 연구에서는 천연물 유래 14종 단일 성분과 합성 화합물 2종을 대상으로 망막질환 개선 가능성을 평가하기 위해, 사람 유래 망막 색소상피 세포를 대상으로 산화적 스트레스에 의한 세포 손상에 대한 보호 효능을 평가하였다. 그 결과, 16종의 후보물질 중 H2O2에 의해 유발된 세포독성을 개선시키는 효능을 보인 5종(auranofin, FK-509, hemistepsin A, honokiol 및 spermidine)을 선별하였다. 이를 기반으로 H2O2에 의한 미토콘드리아 기능 손상 및 활성 저하 억제능을 평가하였으며, auranofin을 제외한 4종에서 유의한 세포 보호 효능이 관찰되었다. 더불어 H2O2에 의해 유도된 DNA 손상에 미치는 영향을 조사한 결과, FK-506, honokiol과 spermidine이 DNA 손상을 개선시켰음을 확인하였다. 그러나 5종의 후보물질이 활성 산소종의 생성에는 뚜렷한 억제 효능을 나타내지 않았으며, 이는 5종의 후보 물질이 ROS-비의존적 기전을 통해 세포 보호효과를 나타낼 것으로 사료된다. 이상의 결과를 바탕으로, 조사 대상 후보물질 중에서 spermidine이 산화적 스트레스로부터 망막 색소상피 세포의 보호 효능이 가장 우수한 천연물 유래 단일 물질임을 규명하였으며, 동시에 합성물질로는 FK-506이 망막 세포 보호 효능이 우수한 것으로 나타났다. 비록 작용 기전에 대한 추가 연구가 필요하겠지만, 본 연구 결과는 spermidine과 FK-506이 산화적 스트레스에 의한 망막질환의 위험을 억제할 가능성이 있음을 시사한다.

• 한국안광학회지
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• 제18권4호
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• pp.525-531
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• 2013

목적: 점안마취제 성분인 proparacaine hydrochloride (PPC)에 의한 결막세포주의 세포자연사와 이에 대한 epigallocatechingallate(EGCG)의 보호효과를 알아보고자 하였다. 방법: 동일한 조건으로 배양된 결막세포주에 Alcaine$^{(R)}$ 0.5%, PPC 0.5%, 그리고 0.01% benzalkonium chloride (BAC)을 각각 15분간 처리한 후, 추가적으로 12시간과 24시간 배양한 후 세 군으로 나누어 MTT assay와 LDH assay를 실시하였다. 배양된 결막세포주에 EGCG를 $10{\mu}M$의 농도로 3시간 동안 전 처리한 후 0.5% PPC를 15분간 추가 배양한 다음 유세포분석기를 이용한 세포자연사 정도를 측정하였다. 결과: Alcaine$^{(R)}$ 0.5%, PPC 0.5%, BAC 0.01%를 15분 동안 처리한 직후와 다시 12시간과 24시간 추가 배양한 결과 모든 군에서 세포생존율이 증가하지 않았다(p<0.05). 0.5% PPC 단독처리군($32.2{\pm}2.0%$)에 비해 $10{\mu}M$의 EGCG 3시간 전 처리하고 PPC 0.5% 후 처리한 군(68.2%)에서 세포 생존율은 더 높아졌다. 또한 PPC 0.5% 처리한 군에서 유도된 세포자연사는 EGCG 첨가로 감소되었다. 결론: 점안마취제인 PPC에 EGCG를 전처리함으로써 세포생존율을 증가시키고, 세포자연사를 억제함으로서 EGCG는 세포보호 효과가 있는 것으로 나타났다.

• 약학회지
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• 제56권2호
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• pp.99-107
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• 2012

The protective effect of AI-1367 (Alnus japonica extract) on liver injury was investigated. Primary rat hepatocyte intoxication was induced by tert-butyl hydroperoxide (tBH), carbon tetrachloride ($CCl_4$), or D-glactosamine (D-GalN). Liver injury was induced by $CCl_4$, D-GalN or MCD (methionine choline deficient)-diet in mouse. The cellular leakage of lactate dehyrogenase and cell viability followed by the treatment of hepatotoxicants were significantly improved by AI-1367 treatment at a concentration range of 5~50 ${\mu}g/ml$ for tBH, 5~50 ${\mu}g/ml$ for D-GalN, and 5~100 ${\mu}g/ml$ for $CCl_4$, respectively. Treatment with AI-1367 (20, 10, 5 mg/kg, p.o.) on liver injury induced by subcutaneous injection of $CCl_4$ or D-GalN reduced significantly the levels of aspartate transaminase and alanine transaminase in serum. Histological observations revealed that fatty acid changes, hepatocyte necrosis and inflammatory cell infiltration in $CCl_4$ (D-GalN)-induced liver injury was improved by administration of AI-1367. AI-1367 treatment (10, 5, 2.5 mg/kg, p.o.) also significantly recovered the body weight change and serum levels of aspartate transaminase, alanine transaminase and triglyceride in liver injury induced by MCD diet. From these results, AI-1367 shows protective effects against tBH, $CCl_4$, D-GalN, or MCD diet-induced hepatotoxicity in vitro or in vivo.

• 동아시아식생활학회지
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• 제24권3호
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• pp.359-367
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• 2014

This study analyzed phytochemicals, including various carotenoids, tocopherol and L-ascorbic acid, in green, yellow and orange paprikas (GP, YP and OP) and measured the preventive effects of lipophilic extracts from different colored paprikas on the blockage of gap junctional intercellular communication (GJIC), which is known as a cellular event associated with tumor promotion. Main carotenoids were lutein and ${\beta}$-carotene in GP, lutein, ${\beta}$-carotene, capsanthin, violaxanthin, ${\beta}$-carotene and capsorubin in YP, and lutein, ${\beta}$-carotene, cryptoxanthin and zeaxanthin in OP. Total carotenoid contents were $65.54{\pm}15.87$ mg/100 g dw in OP, $11.98{\pm}0.69$ mg/100 g dw in YP and $10.30{\pm}1.43$ mg/100 g dw in GP. Tocopherol contents were highest in GP compared with in YP and OP, whereas L-ascorbic acid contents were very high in all paprikas. We determined the non-cytotoxic levels of paprika extracts by MTT assay, which showed less formation of reactive oxygen species (ROS) induced by $500{\mu}M$ $H_2O_2$ for 1h. Finally, we showed that pretreatment of paprika extracts prevented inhibition of GJIC induced by $500{\mu}M$ $H_2O_2$ by the scrape-loading/dye-transfer technique. In conclusion, each colored paprika has unique phytochemicals and showed a protective effect on inhibition of GJIC.

• 생약학회지
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• 제46권2호
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• pp.116-122
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• 2015

Keratinocytes are first barrier against outer challenges on skin. However, it is still largely unknown about effective protectors against ultraviolet B (UVB), and oxidative stress in human keratinocyte, HaCaT cells. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a role in the pathogenesis of skin disorders. Therefore, the purpose of this study was to evaluate the effect of Portulaca oleracea 70% EtOH extracts against hydrogen peroxide (H₂O₂)-induced oxidative stress in human keratinocytes, HaCaT cells. P. oleracea 70% EtOH extracts showed the potent protective effects on H₂O₂-induced toxicity by induced the expression of HO-1 in human keratinocyte, HaCaT cells. Furthermore, P. oleracea 70 % EtOH extracts caused the nuclear accumulation of nuclear factor E2-related factor 2 (Nrf2) in human keratinocytes, HaCaT cells. In addition, we found that treatment with c-Jun N-terminal kinase (JNK) inhibitor (SP600125) reduced P. oleracea 70% EtOH extracts-induced HO-1 expression, and JNK inhibitor (SP600125) also inhibited protective effects by P. oleracea 70% EtOH extracts. Therefore, these results suggest that P. oleracea 70 % EtOH extracts increases cellular resistance to H₂O₂-induced oxidative injury in human keratinocyte, HaCaT cells, presumably through JNK pathway-Nrf2-dependent HO-1 expression.