• Applied Biological Chemistry
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• 제45권4호
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• pp.195-202
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• 2002

국내외에서 수집 재배한 29품종 유색미의 70% 에탄올 추출물로 세포독성, 변이원성, 화학적 직접변이원 mitomycin C, 4-nitroquinoline-N-oxide, 2,4,7-trinitro-9-fluorenone에 대한 항변이원성을 측정하였다. 세포 내재성 alkaline phosphatase활성을 지표로 유색미 추출물이 지시세포인 E. coli PQ 37의 성장에 미치는 영향을 조사한 결과 Jumlalocal, Jumlalocal-1을 포함하는 13종류의 유색미 추출물이 세포독성을 나타낸 반면 DK 1, SC-5, LK 1A-2-12-1-1및 wx 139-3-64-20-3-1등의 품종은 세포성장 촉진활성을 나타내었다. SOS chromotest 기법을 이용하여 유색미가 가지는 변이원성 및 항변이원성을 조사한 결과에서는 Jumlalocal-1, IR 17491-5-4-3-3 및 Jumlalocal 등의 품종이 변이원성을 유도하는 품종이었다. 화학적 직접변이원 mitomycin C, 2,4,7-trinitro-9-fluorenone 및 4-nitroquinoline-N-oxide 에 대해서 공통적으로 항변이원성 효과가 인정되는 유색미 품종은 LK1-3-6-12-1-1, Parnkhari 203, Jumlalocal, wx 139-3-64-20-3-1, Muthumanikam, HP 883-1-1-1-B-1-1, Jumla-local-1 등 7품종이었다.

• 대한의생명과학회지
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• 제24권1호
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• pp.50-54
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• 2018

N-nitroso-N-methylurea (NMU) and N-nitroso-N-ethylurea (NEU), direct alkylating chemical mutagens and carcinogens, are shown to be the upregulators of cellular $NF-{\kappa}B$, regulating various genes that mediate tumorigenesis and carcinogenesis. Nitric oxide (NO), a toxic reactive radical gas, has been known to induce programmed cell death or apoptosis in various cells. Therefore, the assessment of NO production was examined to elucidate the possible contribution of NO release to the chemical carcinogenic potency of NMU and NEU in human skin cells. NMU and NEU did not alter the NO production, but they caused a significant downregulation of the NO generation on lipopolysaccharide (LPS)-induced NO production at concentrations ranging from $2{\sim}5{\mu}M$. The degree of downregulation of NO by NMU and NEU decreased up to 15% and 20%, respectively, compared to the control. These results demonstrate that the LPS-inducible keratinocytes NO synthase is involved in modulating carcinogenic potency by NMU and NEU, and the regulation of the cellular $NF-{\kappa}B$ activity by NMU and NEU is negatively correlated with the level of LPS-induced NO production in human skin cells. The findings of this study suggest the hypothesis that NMU and NEU-induced carcinogenesis may be associated with the downregulation of NO production, and the inducible NO may play an important role in NMU and NEU-induced carcinogenicity in human epidermal keratinocytes.

• 한국환경성돌연변이발암원학회지
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• 제15권2호
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• pp.131-139
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• 1995

Air suspedned particulates are the most serious factor among air pollutants in Seoul and their extracts have been revealed to be pulmonary carcinogenes. Air particulates were collected at a site representative of the high traffic area of Seoul from December 1993 to May 1994. Polycyclic aromatic hydrocarbons (PAHs) and nitroarenes in organic extracts of air particulates were determined by gas chromatography and mutagenicity of particle extracts was evaluated by the pre-incubation procedure with Salmonella typhirnurium TA98 and TA 98NR. The average concentration of total suspended particulates and inhalable (less than 10 $\mu$m) particulates were 169.63 $\mu g/m^3$, 141.92 $\mu g/m^3$, respectively. The relative contribution of organic matters was highest in neutral fraction and was lowest in basic fraction. Among identified 20 PAHs, the level of PAHs with 4-benzen ring i.e., pyrene, benzo(a)anthracene and chrysene were much higher than the PAHs with higher ring numbers. The mutagenicity of air particulates was much higher in the presence of rat liver microsomai fraction (S9 mixture) than that observed in its absence, which indicates that air particulates contained both direct and indirect mutagens. Nitroarenes in this study were not almost detected but mutagenicity of their fraction was higher. These results are represent to research for the identification of nitroarenes in the forward study.

• Journal of Applied Biological Chemistry
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• 제56권4호
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• pp.191-197
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• 2013

To classify the chemical hazard according to globally harmonized system of classification and labeling of chemicals (GHS), we investigated the genotoxicity of three chemicals, methyl myristate, 2-ethylhexanoic acid zinc salt, N,N,N',N'-tetrakis(2-hydroxyethyl) ethylenediamine, using male ICR mice bone marrow cells for the screening of micronucleus induction. Although these three chemicals have already been tested numerous times, a micronucleus test has not been conducted. The seven week-old male ICR mice were tested at three dosages for the three chemicals, respectively. After 24 h of oral administration with the three chemicals, the mice were sacrificed and their bone marrow cells were prepared for smearing slides. As a result of counting the micronucleated polychromatic erythrocyte (MNPCE) of 2,000 polychromatic erythrocytes, all treated groups expressed no statistically significant increase of MNPCE compared to the negative control group. There were no clinical signs related with the oral exposure of these three chemicals. It was concluded that these three chemicals did not induce micronucleus in the bone marrow cells of ICR mice, and there was no direct proportion with dosage. These results indicate that the three chemicals have no mutagenic potential under each test condition, and it is not classified these chemicals as mutagens by GHS.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9517-9522
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• 2014

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and flavonoids, while the hexane extracts contained large amount of tocols and ${\gamma}$-oryzanol. None of the extracts were mutagenic in Salmonella typhimurium strains TA98 and TA100. The hexane extract of rice hull and the methanol extract of rice seed were strongly effective against aflatoxin B1- and 2-amino-3, 4 dimethylimidazo (4, 5-f) quinoline-induced mutagenesis, while aqueous extracts showed weakly antimutagenic properties. All extracts with the exception of aqueous extracts enhanced the number of revertant colonies from benzo (a) pyrene induced-mutagenesis. None of the extracts inhibited mutagenesis induced by the direct mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and sodium azide. The hull extracts showed more potent antimutagenicity than the seed extracts. Based on a chemical analysis, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the hull and cyanidin-3-glucoside and peonidin-3-glucoside in the seed are candidate antimutagens in purple rice. The antimutagenic mechanisms of purple rice might be related to either modulation of mutagen metabolizing enzymes or direct attack on electrophiles. These findings supported the use of Thai purple rice as a cancer chemopreventive agent.

• 한국환경성돌연변이발암원학회지
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• 제9권1호
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• pp.1-12
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• 1989

특정 발암원의 조직특이성 암유발기전을 연구하기 위하여 DMBA의 구강투여 또는 NMU의 동맥주입에 의하여 유암이 유도되는 실험모델을 대상으로 선택하였다. 본 실험에서는 화학적 발암원의 유암유발기전에 미치는 숙주인 흰쥐의 연령효과를 아울러 비교분석하였으며, 특히 발암원의 조직내 활성화, 불활화 및 해독 그리고 DNA 손상과 수성등의 변화를 구명하였다. 유암의 발생율은 1년생 흰쥐보다 생후 50일 흰쥐에서 현저하게 높았다. 특정조직의 선택적 발암기전을 설명하는 기전의 일환으로 조직 DNA의 특정 발암원에 의한 공유결합성 지표(covalent binding index, CBI)를 발암원의 활성화 기전 지표로는 cytochrome P450의 함량을 반면 불확화의 지표로는 glutathione S-transferase와 peroxide의 활성을 비교하였다. 조직의 CBI는 생후 50일군의 유선조직이 DMBA나 NMU에 대하여 간조직보다 유의하게 높았으며 시험관내 CBI 실험에서는 생후 50일군 유선조직의 microsome 분획의 발암원 활성화능이 보다 높음을 관찰하였다. 또한 T.C.D.D. 의존성 cytochrome P450 함량도 생후 50일군에서 가장 높았다. 그러나 불활화 효소들은 연령 변화에 따라 유의한 변화를 보여주지 않았다. 상기의 결과들은 DMBA나 NMU와 같은 발암물질이 특정조직, 특히 유선조직에 생후 50일군에서 유암을 선택적으로 유발하는 기전은 표적 조직의 높은 발암원 활성화능, 낮은 불활화등 그리고 효율이 낮은 DNA 수선능이 연계적으로 작동함으로써 이루어지고 있음을 보여주고 있다.