• Journal of Ginseng Research
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• 제16권3호
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• pp.210-216
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• 1992

The effect of saponin extracted from Panax grneng CA Meyer on DNA repair and replicative DNA synthesis were examined in CHO-Kl cells cotreated with benzo(a)pyrene and rat liver S-15 fraction. The DNA strand breaks inititated by benzo(a)pyrene metabolites were measured by alkaline election technique. The addition of ginseng saponin to the culture media resulted in decrease of benzo(a)pyrene-induced DNA strand breaks, and restored the suppressed-semiconservative-DNA-synthesis by the carcinogen. DNA repair synthesis in the damaged cells was also elevated by the ginseng treatment when the repairing activites were measured for the (3H)-thymidine incorporation into the carcinogen damaged cellular DNk Comparative analysis of DNA-adduces of benzo(a)pyrene metabortes in microsomes suggested that ginseng saponin treatment in rats reduced the formation of electrophilic metabolites of benzo (a)-pyrene in the rat liver microsomes.

• 한국양식학회지
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• 제16권3호
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• BMB Reports
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• 제28권1호
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• pp.1-5
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• 1995

The effect of 6-sulfooxymethyl benzo(a)pyrene (SMBP) on conformational changes of calf thymus DNA was investigated. As SMBP is a strong electrophile, the covalent binding of SMBP to DNA should distort three dimensional conformation of DNA at the binding sites. A formaldehyde-unwinding methods were used to determine the rate of DNA denaturation. The increase in absorbance at 251nm was detected by addition of formaldehyde following treatment with SMBP. SMBP changed supercoiled DNA to relaxed and linear DNA as determined by electrophoresis, which was similar to the change in DNA due to in vitro treatment with benzo(a) pyrene diol epoxide. Treatment with SMBP completely denatured DNA under alkaline conditions. However, DNA was nicked or partially denatured under neutral condition. The absorption band of DNA was increased by the treatment with SMBP in V79 cells, which may be explained by the formation of stabilized SMBP-DNA adduct.

• Molecular & Cellular Toxicology
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• 제2권2호
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• pp.114-119
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• 2006

Benzo[a]pyrene is a representative ecotoxicant in marine environment and a model compound of polycyclic aromatic hydrocarbons, which has an ability to bioaccumulate in aquatic organisms. This study aimed to identify molecular biomarkers suitable for assessing environmental pollution using a microarray technique. We examined the effects of benzo[a]pyrene on gene expressions in the rockfish, Sebastes schlegeli. We constructed the subtractive cDNA library with hepatic RNA from benzo[a]pyrene-exposed and non-exposed control fish. From the library 10,000 candidate clones were selected randomly and cDNA microarray was constructed. We determined benzo[a]pyrene-responsive genes using a high-density microarray. Statistical analysis showed that approximately 400 genes are significantly induced or reduced by benzo[a]pyrene treatment ($2\;{\mu}m$). Especially gene expression changes of 4 candidate clones among the up- or down-regulated genes were investigated in 6, 12 and 24 hr BaP-exposed fish groups. Many methods have been developed to monitor marine environmental status, which depend on quantifying the levels of the toxic components in polluted seawater or on ecological accessing, such as species diversity or richness. However, those methods could not provide information on physiological or genetic changes induced by such environmental stresses. Comparing with the conventional methods, these data will propose that benzo[a]pyrene-responsive genes can be useful for biological risk assessment of polycyclic aromatic hydrocarbons on marine organism at molecular level.

• Journal of Ginseng Research
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• 제13권1호
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• pp.37-41
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• 1989

Benzo(a)pyrene(BP)의 monooxygenase(AHH)에 의해서 생성된 반응성 대사물질들의 in vitro DNA와의 결합 및 BP 대사에 관여하는 효소들의 활성도에 미치는 인삼 물추출물의 영향을 조사하였으며, DNA-BP metabolite adduct들은 Sephadex LH-20 column으로 chromatography하여 5개의 major peak 들을 얻었다. 이 peak 들을 극성이 큰 순서대로 A부터 E까지 임의로 정하고 5개의 peak들을 7,8-diol-9,10-oxide(A), 7,8-oxide(B). 4,5-oxide(C), 9-HO-BP(D & E) adduct들로 잠정적으로 확인하였다. Peak A, C, D 그리고 E는 각각 대조군의 30, 15, 20 그리고 30%로 감소되었으며 peak B는 의미있는 변화를 보이지 않았다. DNA-BP 결합 억제와 관련하여 in vitro와 in vivo 투여시의 경향이 유사하여 EH의 활성도만 BP투여 대조군보다 38%정도 의미있게 유도되었다.

• 생명과학회지
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• 제8권4호
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• pp.400-409
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• 1998

Formation of adduct was studied in benzo(a)pyrene(BP)- and doxorubicin(Dx)-treated human NC-37 cells and isolated nuclei. Major adducts formed were determined by fluorescence absorption spectrophotometery and DNA-lin-ked protein assay. When isolated nuclei were exposed to carcinogens BP and DMBA, and anticancer drugs m-AMSA, ellipticine and Dx, varying degrees of adduct formation occured between DNA-protein complex and these drugs. When the mixture was centrifuged 1.7 M sucrose solution, binding BP and DMBA appeared to be similar between the sediment and the supernatant. When the sediment was centrifuged again with 0.35% polymin-P, the amount of BP bound was 2-fold greater in the protein(1077$\pm$55cpm) than in DNA fraction (470$\pm$20cpm), whereas that of DMBA was 1.6-fold greater in the DNA than in protein fraction. In the case of m-AMSA, ellipticine and Dx, the amount of binding was slightly greater in supernatant than in sediment in centrifugation with 1.7 M sucrose, and more than 3 times greater in the DNA- than in protein- fraction in centrifugation with 0.35% polymin P. DNA fractions which associated with a subset of nonhistone chromosomal protein were isolated from NC-37 cells exposed to $^{3}$H-BP and $^{14}$C-Dx. They were separated into two distince components DNA-S and DNA-P by centrifugation with 2M Nacl chromatin extraction. The results indicated that the amount of $^{3}$H-BP bound was 6.0-fold greater in DNA-P as compared with DNA-S, while that of $^{14}$C-Dx binding appreaed to be 6.2-fold greater in DNA-S than in DNA-P fraction. When $^{3}$H-BP binding wasdetermined in the presence of cold Dx, the amount of binding was reduced only in the DNA-P fraction, indicating that the interaction between DNA and protein is decreased. Gene expression by these drugs, BP treated cells were increased to compare with nomal cells but reduced by treatment with BP-Dx. These results suggest that the protein moiety which tightly bound to DNA-P fraction may play an important role in the regulation of gene expression.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3015-3020
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• 2014

The behavior of benzo[a]pyrene-7,8-dione (BPQ) in aqueous solution and its interaction with native DNA was investigated using conventional absorption and linear dichroism (LD) spectroscopy. The appearance of a broad absorption maximum at long wavelengths and its proportional relationship to solvent polarizability suggested that BPQ adopts a aggregated state for all solutions examined. Disappearance of this absorption band at higher temperatures in aqueous solution also supported BPQ aggregation. When associated with DNA absorption spectral properties were essentially the same as that in aqueous solution. However, two isosbestic wavelengths were found in the concentration-dependent absorption spectrum of the BPQ-DNA complex, suggesting the presence of at least two or more DNA-bound BPQ species. Both species produced $LD^r$ spectra whose magnitude in BPQ absorption region is larger or comparable to that in the DNA absorption region, suggesting that the molecular BPQ plane is near perpendicular relative to the local DNA helical axis. Therefore, BPQ molecules are aligned along the DNA stem in both DNA-aggregated BPQ species.

• 한국환경성돌연변이발암원학회지
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• 제18권2호
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• pp.71-76
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• 1998

환경독성물질에 의한 폭로는 세포내 DNA의 수복과정에 영향을 미쳐 돌연변이나 암을 유발할 수 있다. 독성물질에 의해 유도된 DNA의 비정상 수복효과를 판단하기 위하여.in vivo에서 MNNG 또는 Benzo(a)pyrene을 투여하고 in vitro에서 Bleomycin을 처리하여 나타나는 염색체이상효과를 관찰하였다. 실험결과, MNNG를 투여 후 Bleomycin을 처리하였을 때 염색체이상의 상승효과가 나타났다. 한편, Benzo(a)pyrene 투여 후 Bleomycin을 처리하였을 패는 높은 농도에서 염색체이상의 상승효과가 나타났다. 이같은 결과는 MNNG나 Benzo(a)pyrene 같은 유전독성물질들이 in vivo에서 세포내 비정상 DNA수복을 일으킬 수 있으며, 이러한 작용은 관련 유전독성물질의 염색체손상성에 무관하며 투여용량에 의존되는 것으로 판단된다.

• 한국환경보건학회지
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• 제40권1호
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• pp.55-62
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• 2014

Objectives: $^{32}P$-postlabeling assay is the most sensitive method of detecting DNA adduct formation. However, it is limited by a low sample throughput and use of radioisotopes (RI). In this study, we modified it to minimize these limitations and applied it to Z. platypus exposed to Benzo(a)pyrene (BaP) in order to investigate DNA adduct formation (effect biomarker for pollutants) in Z. platypus for assessing risk of waterborne BaP exposure. Methods: DNA hydrolysis was performed only with Micrococcal nuclease (MNase), RI reduction test was performed and the overlapping steps between thin layer chromatography (TLC) and radioisotope high-performance liquid chromatography (RI-HPLC) were omitted. The application of a modified method to Z. platypus exposed to BaP was performed. Results: The results revealed that the amount of RIs used can be reduced roughly 10-fold. Because the analysis time was shortened by 8.5 hours, the sample throughput per hour was increased compared with the previous method. The results of applying modified $^{32}P$-postlabeling assay to Z. platypus, DNA adduct formation in Z. platypus showed dose-dependency with the BaP concentration. Only BPDE-dGMP was detected as a DNA adduct. Conclusion: These results demonstrate that the modified $^{32}P$-postlabeling assay is a suitable method for detecting DNA adduct formation in Z. platypus exposed to waterborne BaP and will be useful in risk assessment of carcinogenic effect in aquatic environment due to BaP.

• Korean Journal of Acupuncture
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• 제19권1호
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• pp.7-13
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• 2002

1. 천궁약침액은 1${\times}$에서 15.1%의 cytochrome P4501A1 저해효과를 나타냈으며 그 억제효과는 약침액의 농도가 높을수록 증가하였다. 2 천궁약침액은 benzo[a]pyrene과 세포의 DNA 결합을 유의성있게 억제시켰다. 이상의 결과를 종합해 볼때 천궁약침액은 효과적으로 cytochrome P4501A1 효소를 저해했으며, 발암물질과 DNA의 결합을 억제시켜 외부 물질 또는 대사물에 의해 일어날 수 있는 돌연변이와 암 발생을 억제할 것으로 사료된다.