• Journal of Ginseng Research
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• v.16 no.3
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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.

• Journal of Environmental Health Sciences
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• v.40 no.1
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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.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.42-48
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• 1989

The binding of bay region diol-epoxides of polycyclic aromatic hydrocarbons (PAHs) to target tissue DNA is thought to be essential for the initiation of cancer by these compounds. In this study we investigated the effect of polyacetylenes such as panaxynol and panaxydol on the formation of benzo(a)pyreno (BP)-metabolite-DNA adduct in the liver of ICR mice. Treatment of mice by i.p. administration of polyacetylenes produced a marked reduction in BP metabolite binding to DNA in vitro. Following i.v. administration of (3H)BP(300, ${\mu}$Ci/21 nmoles/0.1 nt DMSO) to mice, radioactivity was detected in the DNA of the liver in vivo. The result of tentative identification of the 4 peaks between the two standard markers for high pressure liquid chromatography showed that the peaks. I, II, III, and IV were BP-phenol oxide-DNA adduct (or BP-diol-epoxide-dCyt. adduct), (-) BP$.$diolepoxide I:dGuO adduct, (+) BP-diol-epoxide I: dGuo adduct, and BP-diol-epoxide II:dGuO adduct, respectively. The minor adduct, (-) BP-diol epoxide I: dGuo was reduced to 6971 of the amount of the control, while the major adduct, (+) BP-diolepoxide I: dGuO(peak II) which was produced from (-) BP-7, 8-diol was reduced to 78% of that of the control. The amount of the minor adduct, BP-diol-epoxide II:dGuo adduct(peak IV) which formed from (+) BP-7, 8-diol was 58% of the control. These results show that the panaxydol is more related to inhibition of the formation of the minor ad- ducts than of the major adducts, which were generally produced from ($\pm$) BP-7, 8-dihydro-dials.

• BMB Reports
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• v.28 no.1
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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.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.37-41
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• 1989

Reactive metabolites generated by benzo(a)pyrene(BP) monooxygenase(AHH) interact with nucleophiles in DNA and cause mutation and carcinogenesis. We studied the effect of Panax ginseng C.A. Meyer, which induce epoxide hydratase(EH) activity without concomitant induction of AHH activity, on the binding of BP metabolites to DNA in uitro in Sprague Dawley rats. DNA-BP metabolite adducts can be resolved into at least five distinct peaks by elution of a Sephadex LH-20 column with a water methanol gradieNt. These peaks are arbitrarily designated A(most polar) through I(least polar). Of the 5 peaks tentatively assigned to 7,8 biol-9,10-oxide(A),7,8·oxide(B),4,5-oxide(C), and further metabolites of 9-OH-BP(D & E), peaks A, C, D, and I were reduced to 70, 85, 80, and 30% of controls, respectively, and there was no significant change in peak B. In connection with this DNA binding study, BP metabolizing enzymes including AHH, EH, demethylase(DM) activity and cyt. P-450 contents were also investigated in order to compare the BP treated control with ginseng and BP treated test groups. The results showed that the EH activity was increased by 139% over the BP control, the Cyt. P-450 content was increased by 180% over the control value, and DM and AHH activities were also increased to some degree for the BP test group, but there was no significant effect of the ginseng treatment.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.297-302
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• 2003

Cnidii Rhizoma water extract (CRW) was tested for liver cancer chemopreventive potential by measuring the inhibition of phase I enzyme and benzo[a]pyrene-DNA adduct formation and induction of phase II detoxification enzymes. There was 17.0% inhibition in the activity of cytochrome P450 1A1 enzyme with the treatment of 150 mg/ml CRW. At concentration of 30 mg/ml CRW, the binding of $[^3H]B[a]P$ metablites to DNA of NCTC-clone 1469 cell was inhibited by 33.3%. CRW was potent inducer of quinone reductase (QR) and glutathione S-transferase (GST) activities in cultured murine hepatoma Hepalc1c7 cells. However, hepatic glutathione (GSH) level was not influenced by CRW. These findings suggest that CRW has chemopreventive potential of liver cancer by inhibiting cytochrome P450 1A1 activity and benzo[a]pyrene-DNA adduct formation and inducing QR and GST activities.

• Korean Journal of Acupuncture
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• v.19 no.1
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• pp.7-13
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• 2002

The effects of Cnidium officinale Makino aqua-acupuncture solution (COMAS) and Cnidium officinale Makino water-extraced solution (COMWS) on the CYP1A1 activity and benzo[a]pyrene(B[a]P)-DNA adduct formation were examined. There were 6.8%, 12.1%, 15.1%, 18.3% and 22.6% inhibition in the activity of cytochrome 4501A1 enzyme with the treatment of $0.1{\times},\;0.5{\times},\;1{\times},\;3{\times},\;and\;5{\times}$ COMAS, respectively. At concentration of $0.1{\times}$ COMAS, the binding of $[^3H]B[a]P$ metabolites to DNA of NCTC-clone 1469 cell was significantly inhibited by 56.9%. These results suggest that COMAS has chemopreventive potential by inhibiting cytochrome P4501A1 activity and benzo[a]pyrene-DNA adduct formation.

• Journal of Life Science
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• v.8 no.4
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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.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05b
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• pp.20-45
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• 2002

In this study, we demonstrated the in vitro and in vivo formation of carcinogen-lipid adduct and its correlation with DNA or protein adducts. The lipids from serum or hepatocyte membranes of Spragu-Dawley rats. human serum, and standard major lipids were in vitro reacted with benzo[a]pyrene(BP) and BP metabolites. 7,8-Dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]-pyrene(BPDE-I), an ultimate carcinogenic form of BP, was covalently bound to triglyceride(TG). BPDE-I-TG adducts isolated by thin-layer chromatography (TLC) were further detected by high performance liquid chromatography(HPLC). TGs, including triolein, tripalmitin and tristearin, showed positive reactions with BPDE-I. However, cholesterol, phospholipids(Phosphatidylcholine, phosphatidyl-ethanolamine, phosphatidyl-inositol and sphingomyelin) and nonesterified fatty acids(palmitic acid, oleic acid, linoleic acid and stearic acid) did not react with BPDE-I. In addition, other BP metabolites (BP-phenols and -diols) did not react with TG, which TG appeared to be the most reactive lipid yet studied with respect to its ability to form an adduct with BPDE-I. There was a clear-cut dose-respect to its ability to form an adduct with BPDE-I-lipid adduct in vitro between TG and [1,3-3H]BPDE-I. In an animal study, BPDE-I-TG was also formed in the serum of rats orally treated with BP(25 mg/rat). Also, obvious correlations between [3H]BP related-biomolecule adducts (DNA, protein) or lipid damage and the BPDE-I-TG adduct were obtained in various tissues of mice i.p. treated with [3H]BP. These data suggest that TG can form an adduct with BPDE-I, as do other macromolecules (DNA, RNA, and protein). Therefore, a carcinogen-lipid adduct would be a useful biomarker for chemical carcinogenesis research and cancer risk assessment.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2000.12a
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• pp.74-74
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• 2000