• Molecules and Cells
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• v.19 no.1
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• pp.114-123
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• 2005

Nitropyrene, the predominant nitropolycyclic hydrocarbon found in diesel exhaust, is a mutagenic and tumorigenic environmental pollutant that requires metabolic activation via nitroreduction and ring oxidation. In order to determine the role of ring oxidation in the mutagenicity of 1-nitropyrene, its oxidative metabolites, 1-nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide, were synthesized and their mutation spectra were determined in the coding region of hprt gene of CHO cells by a PCR amplification of reverse-transcribed hprt mRNA, followed by a DNA sequence analysis. A comparison of the two metabolites for mutation frequencies showed that 1-nitropyrene 9,10-oxide was 2-times higher than 1-nitropyrene 4,5-oxide. The mutation spectrum for 1-nitropyrene 4,5-oxide was base substitutions (33/49), one base deletions (11/49) and exon deletions (5/49). In the case of 1-nitropyrene 9,10-oxide, base substitutions (27/50), one base deletions (15/50), and exon deletions (8/50) were observed. Base substitutions were distributed randomly throughout the hprt gene. The majority of the base substitutions in mutant from 1-nitropyrene 4,5-oxide treated cells were $A{\rightarrow}G$ transition (15/33) and $G{\rightarrow}A$ transition (8/33). The predominant base substitution, $A{\rightarrow}G$ transition (11/27) and $G{\rightarrow}A$ transition (8/27), were also observed in mutant from 1-nitropyrene 9,10-oxide treated cells. The mutation at the site of adenine and guanine was consistent with the previous results, where the sites of DNA adduct formed by these compounds were predominant at the sites of purines. A comparison of the mutational patterns between 1-nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide showed that there were no significant differences in the overall mutational spectrum. These results indicate that each oxidative metabolite exhibits an equal contribution to the mutagenicity of 1-nitropyrene, and ring oxidation of 1-nitropyrene is an important metabolic pathway to the formation of significant lethal DNA lesions.

• BMB Reports
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• v.41 no.8
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• pp.604-608
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• 2008

1-Nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide are oxidative metabolites that are responsible for the mutagenicity of 1-nitropyrene. In this study, the mutation spectra induced by oxidative metabolites in human cells were determined using a shuttle vector assay. The mutation frequencies induced by 1-nitropyrene 9,10-oxide were 2-3 times higher than those induced by 1-nitropyrene 4,5-oxide. The base substitutions induced by 1-nitropyrene 4,5-oxide were $G{\rightarrow}A$ transitions, $G{\rightarrow}C$ transversions, and $G{\rightarrow}T$ transversions. In the case of 1-nitropyrene 9,10-oxide, $G{\rightarrow}A$ transitions, $G{\rightarrow}T$ transversions, $A{\rightarrow}G$ transitions and $G{\rightarrow}C$ transversions were observed. Most base substitution mutations induced by oxidative metabolites occurred at the guanine sites in the supF gene. These sequence-specific hot spots were commonly identified as 5'-GA sequences for both metabolites. On the other hand, the sequence-specific hot spots at the adenine sites were identified as 5'-CAC sequences for 1-nitropyrene 9,10-oxide. These results suggest that the oxidative metabolites of 1-nitropyrene induce sequence-specific DNA mutations at the guanine and adenine sites at high frequency.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.114-120
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• 1991

대기부유입자상물질이나 diesel 배출가스중에 함유하여, 주요한 direct-acting mutagen의 하나로 작용하는 1-nitropyrene, 1,3-, 1,6- 및 1,8-dinitropyrene을 합성하고, 고속액체 chromatography로 분리정제하여, Salmonella typhimurium TA 98, S9mix 비첨가의 계에서 돌연변이원성을 측정한 결과, 1-nitropyrene에 비하여, dinitropyrene은 강력한 돌연변이 원성을 나타내었고, 그 중에서도 1,8-dinitropyrene은 733,000 revertants/$\mu$g으로 최고의 돌연변이원 활성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.869-876
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• 2022

The skin, which is the largest organ of the human body, is in direct contact with pollutants in the surrounding atmosphere. Meanwhile, 1-nitropyrene (1-NP), the most abundant nitro-polycyclic aromatic hydrocarbon found in particulate matter, is known to have carcinogenic effects; however, studies on its toxicity in human and canine skin are still needed. In this study, we investigated 1-NP-induced apoptosis and inflammatory pathways in HaCaT cells. In addition, we also measured the cytoprotective effect of methyl gallate (MG), which is widely distributed in medicinal and edible plants and is well known for its anti-inflammatory and antioxidant properties. MG inhibited 1-NP-induced cell death and apoptosis pathways, including the cleavage of PARP and activation of caspase-3, -7, and -9. MG also suppressed 1-NP-induced COX-2 expression and phosphorylation of mitogen-activated protein kinases (MAPKs) and MAPK kinases (MAPKKs). Our findings suggest that 1-NP induces skin toxicity in human and canine through apoptosis and inflammatory responses, and moreover, that this can be prevented by treatment with MG.

• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.1-8
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• 2010

The effectiveness of the government regulation on tail-pipe emission for diesel vehicles issued in 2003 in Tokyo was evaluated in this study. Variations in annual average concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs associated with airborne particulate matter were investigated in connection with the variation in airborne elemental carbon (EC) concentration in downtown Tokyo, Japan in 2006-2007 and in 1997-1998. The annual average concentrations of EC, seven different PAHs, and 1-nitropyrene were found to have decreased significantly from 1997-1998 to 2006-2007. The most prominent decrease in atmospheric concentration was observed for 1-nitropyrene, which is a representative nitro-PAH originating from diesel vehicles. This indicated that the government control has worked to considerably reduce both atmospheric mutagens and airborne particulate matter. In contrast, the concentrations of two nitro-PAHs, 2-nitrofluoranthene and 2-nitropyrene, remained the same. These nitro-PAHs are known to be formed by atmospheric nitration of their parent PAHs, and this result suggested factors other than the concentration of parent PAHs and $NO_2$ affects the degree of atmospheric formation of nitro-PAHs.

• Asian Journal of Atmospheric Environment
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• v.5 no.3
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• pp.146-151
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• 2011

1-Nitropyrene (1-NP), 2-NP and 2-nitrofluoranthene (2-NFR) are useful markers for studying the atmospheric behaviors of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs). However, present methods for measuring trace levels of these compounds are lesssensitive and laborious. Here we describe several improvements to a previously reported high-performance liquid chromatography-chemiluminescence detection system that allows it to determine trace levels of 1-, 2-NPs and 2-NFR. The proposed system was equipped with a reducer column packed with Pt/Rh instead of zinc whose life-time was limited. The combination of Cosmosil MS-II (monomeric ODS) and AR-II (polymeric ODS) columns was used instead of polymeric ODS columns as the separator column to improve the separation. An ethanol mixture with acetate buffer (pH 5.5) was used in place of an acetonitrile mixture with the same buffer to activate the reducer column. The same ethanol mixture was used as the mobile phase for the clean-up column. The switching time of the column switching valve was optimized to concentrate the amino-derivatives of above NPAHs quantitatively on the concentrator column. The concentrations of bis(2,4,6-trichlorophenly) oxalate and hydrogen peroxide in the chemiluminescence reagent solution were optimized to 0.4 mM and 30 mM, respectively, to increase the sensitivity. Under the above conditions, the detection limits (S/N=3) of 1-, 2-NPs and 2-NFR were 1 fmol (0.25 pg), 10 fmol (2.5 pg) and 4 fmol (1 pg), respectively. The proposed system was effectively used to determine trace levels of 1-, 2-NPs and 2-NFR in airborne particulates collected at Noto Peninsula. The atmospheric concentrations of 1-, 2-NPs and 2-NFR were not more than sub pg $m^{-3}$ levels. They were higher in winter (January) than in summer (July). In both seasons, the concentrations were in decreasing order, [2-NFR]>[1-NP]>[2-NP].

• KSBB Journal
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• v.18 no.3
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• pp.217-221
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• 2003

Antimutagenic effects og Eleutherococcus senticosus Maxim. on the mutagenicty induced by mutagens, 4-NQO, MNNG, $\textrm{NaN}_{3}$, 2-NF, and 1-NP was studied by the Ames test with Salmonella typhimurium TA98 and TA100. The methanol extract ($500\mu\textrm{g}$/plate) of E. senticosus Maxim. showed inhibitory effect on the mutagenicty induced by 1-NP only among the tested mutagens. In S. typhimurium TA98, the methanol extracts of the root, stem and leaf showed inhibitory effects of 54.9, 29.5, and 32.9% inhibition on 1-NP mutagenicity, respectively. In S typhimurium TA100, the methanol extracts of the root, stem, and leaf showed inhibitory effects of 593, 30.2, and 43.6%, respectively. The methanol extract were further fractionated by a subsequent liquid-liquid partition technique with chloroform, butanol, and water. The chloroform ($300\mu\textrm{g}$/plate) fraction of the root, stem and leaf showed the strong antimutagenic effects on the mutagenicity induced by 1-NP in S typhimurium TA98 and TA100. But none or weak antimutagenicities were observed in the butanol and aqueous fraction. The chloroform fractions of root, stem and leaf showed the antimutagenic effects of 61.6~88.6% in a dose-dependent manner. In the antimutagenic mode test, the inhibition effect of root was mainly bio-antimutagenic, whereas stem and leaf were desmutagenic.

• Environmental Analysis Health and Toxicology
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• v.7 no.3_4
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• pp.69-79
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• 1992

Recently, concerns of water pollution and health risks caused by synthetic detergents have emerged, as the use of various detergents has increased It has been suggested that some surfactants are cocarcinogens. The surfactants tested were linear alkylbenzene sulfonate, sodium lauryl sulfate, polyoxyethylene sorbitan monooleat (tween 80), and the mutagens were 1-nitropyrene, N -methyl- N'-nitro-N -nitrosoguanidine, benzo (a) pyrene, and aflatoxin B$_1$. This study was undertaken to investigate the effects of surfactants on the activity of mytagens using the Ames mutagenic assay with Salmonella typhimurium TA98, TA100. The results were summarized as follows: 1. The surfactants have no mutagenic activity of themselves. 2. Higher doses of surfactants than 100 $\mu\textrm{g}$/plate reduced the number of revertants. It is assumed that the reduction would inhibited cell growth. 3. When the comutagenic ratio is defined as the ratio between mutagenic activity itself and the activity with mutagen and surfactant (drinking water quality standard), LAS showed the comutagenic ratio 0.86-1.17 and SLS 0.74-1.10 as well. According to the comparisons, it could not be recognised for the comutagenicity of drinking water quality standard of surfactant. 4. As increasing the amount of mutagens, the designated amount of surfactant did not affected the mutagen's activity statistically. From the above result, syunthetic surfactants do not present mutagenicity and comutagenicity in the microbial assay.

• Asian Journal of Atmospheric Environment
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• v.1 no.1
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• pp.19-27
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• 2007

Hazardous polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) are mainly originated from imperfect combustion of fossil fuels such as petroleum and coal. The consumptions of not only petroleum but also coal have been increasing in the East Asian countries. This review describes the result of international collaboration research concerning characteristics and major contributors of atmospheric PAHs and NPAHs in cities in Japan, Korea, China and Russia. We collected airborne particulates in ten cities in the above countries and six PAHs and eleven NPAHs were determined by HPLC methods using fluorescence and chemiluminescence detections. The total PAH concentrations were much higher in Chinese cities (Fushun, Tieling, Shenyang and Beijing) than those in other cities (Vladivostok, Busan, Kanazawa, Kitakyushu, Sapporo and Tokyo). The total NPAH concentrations were also higher in Chinese cities than those in the other cities. The [NPAH]/[corresponding PAH] ratios are much larger in diesel-engine exhaust particulates than those in coal-burning particulates. The [1-nitropyrene]/[pyrene] ratio of airborne particulates was much smaller in the four Chinese cities, suggesting that coal combustion systems such as coal heaters were the main contributors. On the other hand, the ratios were larger in Korean and Japanese cities, suggesting the large contribution of diesel-engine vehicles.

• Asian Journal of Atmospheric Environment
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• v.10 no.2
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• pp.90-98
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• 2016

Total suspended particulates (TSP) in the atmosphere were collected for 2 weeks during winter in Muroran, Hokkaido, Japan, a typical iron-manufacturing city. The concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) in TSP were determined by high-performance liquid chromatography (HPLC) using fluorescence and chemiluminescence detectors, respectively. No relationship was observed between the atmospheric PAH and NPAH concentration, or the atmospheric PAH and TSP concentration. However, there was a tendency that the atmospheric PAH concentration was higher when the wind blew from the coke-oven plant. Furthermore, the concentration ratios of 1-nitropyrene to pyrene, which is a suitable indicator of the contribution made by automobiles and coal combustion systems to urban air particulates, were smaller in Muroran and the values were close to those observed in particulates from coal combustion systems. Therefore, these results show that the PAH and NPAH compositions for Muroran are characteristic of an iron-manufacturing city.