• Title, Summary, Keyword: chemopreventive

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INHIBITION OF CYCLOOXYGENASE-2 AND INDUCIBLE NITRIC OXIDE SYNTHASE BY SELECTED CHEMOPREVENTIVE PHYTOCHEMICALS VIA THE NF-$\textsc{k}$ B SIGNALING PATHWAY

  • Surh, Youna-Joon;Chun, Kyung-Soo;Lee, Ji-Yoon;Han, Seong-Su;Keum, Young-Sam;Seo, Hyo-Joung;Lee, Jeong-Hee;Park, Kwang-Kyun;Lee, Sang-Sup
    • Proceedings of the Korean Society of Toxicology Conference
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    • pp.31-32
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    • 2001
  • A wide array of phenolic substances, particularly those present in dietary and medicinal plants, have been reported to possess substantial anticarcinogenic and antimutagenic activities. The majority of naturally occurring phenolics retain antioxidative and anti-inflammatory properties which appear to contribute to their chemopreventive or chemoprotective activity. Inducible cyclooxygenase (COX-2) and nitric oxide synthase (iNOS) are important enzymes that mediate inflammatory processes.(omitted)

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C/EBP$\beta$ mediated inhibition of PAH-inducible CYPlAl expression by Oltipraz, a cancer chemopreventive agent

  • Cho, Il-Je;Kim, Sang-Geon
    • Proceedings of the PSK Conference
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    • pp.85.3-85
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    • 2003
  • Oltipraz, a cancer chemopreventive agent, induces CYP1A1 to a certain extent by transactivation of the gene via the Ah receptor (AhR)-xenobiotic response element (XRE) pathway. Previously, we showed that oltipraz promoted CCAAT/enhancer binding protein (C/EBP ) activation, which leads to the induction of glutathione S-transferase. Given that oltipraz activates C/EBP for gene transactivation and that the putative C/CBP binding site is located in CY)1A1 promoter region, this study investigated the effect of oltipraz on CYP1A1 induction by 3-methylcholanthrene (3-MC). (omitted)

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Inhibitory effects of pinosylvin on prostaglandin E$_2$ and nitric oxide production in lipopolysaccharide-stimulated mouse macrophage cells

  • Park, Eun-Jung;Min, Hye-Young;Kim, Moon-Sun;Pyee, Jae-Ho;Ahn, Yong-Hyun;Lee, Sang-Kook
    • Proceedings of the PSK Conference
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    • pp.194.2-194
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    • 2003
  • The inhibitors of prostaglandin biosynthesis and nitric oxide production by corresponding inducible isozyme have been considered as potential anti-inflammatory and cancer chemopreventive agents. In our continuous search for cancer chemopreventive agents from natural products, we have evaluated the inhibitory potential of PGE$_2$ and NO production in lipopolysaccharide (LPS)-induced mouse macrophage RAW 264.7 cells. As a result, pinosylvin (3,5-dihydroxy-trans-stilbene), a stilbenoid, mainly found from the heartwood and leaves of the Pinus sylvestris, showed potential inhibitory activity of LPS-induced PGE$_2$ and NO production in a dose-dependent manner. (omitted)

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Chemopreventive Effects of Ginseng on Rat Carcinogenesis

  • Wanibuchi Hideki;Ichihara Toshio;Morimura Keiichirou;Fukushima Shoji
    • Proceedings of the Ginseng society Conference
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    • pp.277-287
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    • 2002
  • The chemopreventive effects of ginseng on rat carcinogenesis models were investigated, In the present study, the inhibitory effects of white and red ginseng on tumor development were examined using medium-term liver, initiation and medium-term multi-organ carcinogenicity bioassay systems. No modifying potential of the ginsengs was evident in terms of the numbers or areas of glutathione S-transferase placental form (GST -P)-positive foci, which is a marker of preneoplastic lesion in rat livers. However, white ginseng, but not red ginseng was found to decrease the incidences of adenocarcinoma of the small intestine and colon in the medium-term multi-organ carcinogenesis model. These results indicate that white ginseng may have inhibitory effects on progression stage of rat intestinal carcinogenesis, but the influence is not strong. Ginseng is unlikely to have promoting or inhibitory effects in other organs under the present type of experimental conditions. Possible application on ginseng for chemoprevention of colon cancer in humans, can be concluded given the lack of obvious adverse effects.

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Chemopreventive Effect of Retinoids on Cellular NF-kappaB Activity Induced by Alkylating Carcinogens in Human Epidermal Keratinocytes

  • Cho, Eun-Jeong;Lee, Min-Hee;Kim, Seung-Kyoon;Lee, Young-Jong;Moon, Ki-Young
    • Proceedings of the PSK Conference
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    • pp.171.2-171
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    • 2003
  • Retinoids have been shown to be effective in suppressing tumor development in chemical carcinogens such as N-nitroso-N-methylurea (NMU) and N-nitroso-N-ethylurea (NEU) induced mammary tumors in various animals. However, retinoids-mediated chemopreventive process, linked to transcription factor NF-kappaB activation on chemoprevention has yet to be studied. (omitted)

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Development of TPA-induced Ornithine Decarboxylase (ODC) Inhibitors from Plants as Cancer Chemopreventive Agents

  • Kim, Soo-Jeong;Lee, Ik-Soo;Chang, Il-Moo;Mar, Woong-Chon
    • Natural Product Sciences
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    • v.2 no.2
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    • pp.123-129
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    • 1996
  • Chemical carcinogenesis is associated with the increase of intracellular polyamine levels, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse epidermal ODC activity are essential to skin tumor promotion by TPA. Therefore, for the discovery of new cancer chemopreventive agents, we have evaluated about 73 kinds of natural products to study inhibitory effects against ODC activity induced by TPA in T24 cell culture system. The total methanol extracts of plants fractionated into three layers (hexane, ethyl acetate and water layer) were tested and the hexane fraction of Angelica gigas $(root\;bark,\;IC_{50}:\;7.4\;{\mu}g/ml)$ and the ethyl acetate fraction of Corydalis ternata $(root,\;IC_{50}:\;7.5\;{\mu}g/ml)$ were the most effective on the inhibition of TPA-induced ODC activity, These active fractions are under investigation with further sequential fractionation using column chromatography.

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Antigenotoxicity of Quercetin and its Glycosides (Quercetin 및 Quercetin 배당체들의 유전독성억제효과)

  • 허문영;김정한
    • Journal of Food Hygiene and Safety
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    • v.11 no.2
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    • pp.115-121
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    • 1996
  • In order to compare the suppressive effect of quercetin and several its glycosides, such as quercitrin (quercetin-3-rhamnoside), isoquercitrin (quercetin-3-glucoside), hyperin (quercetin-3-galactoside) and tutin (quercetin-3-rhamnosyl glucoside), on the genotoxicity by N-methyl-N-nitrosourea(MNU), in vitro sister chromatid exchange(SCE) test using mouse spleen lymphocytes and in vivo micronucleus test using mouse peripheral blood were performed. MNU-induced SCEs in vitro were not decreased by the simultaneous treatment of test compounds. Among them, quercetin and hyperin showed significant suppressive effects at high dose(10-5M). On the other hand, MNU-induced micronucleated reticulocytes(MNRETS) in vivo were significantly decreased with good dose-dependent manner in all compound tested. However, there were not significant differences between quercetin aglycone and its glycosides in the suppressive aglycone and its glycosides may act as an antigenotoxic agent in vivo and may be useful as a chemopreventive agent of alkylating agent.

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Effect of Resveratrol on Coxsackie Virus B3m-induced Myocarditis in Mice

  • Dong Hao-Han;He-Li Ren
    • Proceedings of the Korean Society of Food Science and Nutrition Conference
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    • pp.116-121
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    • 2004
  • To observe the intervening effect of resveratrol on coxsackie virus B3m-induced myocarditis in Balb/c mice and explore the mechanism of intervening effect. Using an animal model of viral myocarditis induced by coxsackie virus B3m (CVB3m), with Ribavirin and Astragalan as comparison, to examine the changes of general condition, mortality, the weights of heart, liver and spleen, serum MDA and NO levels, and cardiac histology in Balb/c mice. By comparison with Ribavirin and Astragalan, it was found that in the mice model of viral myocarditis induced by coxsackie virus B3m resveratrol significantly improved the changes of general condition, mortality, the weights of heart, liver and spleen, serum MDA and NO levels, and cardiac histology. It suggested that resveratrol may have some chemopreventive and chemotherapeutic effects in the treatment of viral myocarditis.

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