• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.194-198
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• 2001

The study was conducted to investigate the changes of hepatic cytochrome P450 monooxygenase system induced by dietary administration of polychlorinated biphenyls (PCBs) in the tilapia, Oreochromis niloticus. Tilapia were fed pellet with PCBs (Aroclor 1254) 0.05, 0.25 and 0.50 mg/kg body weight/day for 30 days. The dietary administration of PCBs (0.05 mg/kg) induced a significantly increased the concentration of cytochrome P450 and the activity of 7-ethoxyresorufin-O-deethylase (EROD) in the hepatopancreas at 30 days, while the augmentation of both responses was found at 20 days with a higher administration of PCBs-diet (0.25 mg/kg). However, hepatic 7-penthoxyresorufin-O-dealkylase (PROD) activity did not show any noticeable changes with the PCBs-diet 0.05-0.5 mg/kg range compared to control group during the experimental periods of 30 days in the tilapia. These results indicate that tilapia fed PCBs at the concentration of more than 0.05 mg/kg for 30 days are affected by PCBs in terms of cytochrome P450 concentration and EROD activity in the hepatopancreas.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1405-1409
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• 2006

Polysaccharides from the starfish Asterina pectinifera were assessed in vitro for their chemopreventive potential in human breast cancer. The polysaccharides from A. pectinifera inhibited cell proliferation in the estrogen receptor-positive (MCF-7) and estrogen receptor-negative (MDA-MB-231) human breast carcinoma cell lines. In addition, the polysaccharides were found to be an inhibitor of cytochrome P450 1A1-mediated ethoxyresorufin O-deethylase activity, and caused a dose-dependent inhibition of aromatase activity in microsomes isolated from a human placenta. There was a significant reduction in the ornithine decarboxylase activity to 30.7% of the control in the polysaccharide-treated MCF-7 breast cancer cells. Therefore, the polysaccharides from A. pectinifera merit further investigation with respect to breast cancer chemoprevention.

• Toxicological Research
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• v.9 no.2
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• pp.177-186
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• 1993

Previous results from several laboratories have demonstrated that tumor necrosis factor-alpha (TNFalpha) depressed cytochrome P-450 (P-450)-dependent drug metabolism in vivo. However, there is some debate whether the action of TNFalpha is mediated by its direct effects on hepatocytes, or is indirectly mediated through the release of other mediators like IL-1 from macrophages. In the present studies, we investigated the effects of TNFalpha on P-450-dependent drug metabolizing enzyme as measured by 7-ethoxyresorufin O-deethylase (EROD) activity.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.112.2-112.2
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• 2003

CYP1 enzymes, CYP1A1, CYP1A2 and CYP1B1, are known to bioactivate procarcinogens particularly polyaromatic compounds. Flavonoids are a class of natural compounds that are present in edible plants. Structurally, these compounds are polyphenols with two aromatic rings (A, B) and a heterocycyclic ring (C). We observed the differential inhibition of 5,7-dihydroxyflavones which are different in numbers of B-ring-OH, to the activity of ethoxyresorufin O-deethylase (EROD) in human hepatic microsomes with the IC50 values, ie, 0.57 mM, 1.28 mM, and 3.62 mM, chrysin, apigenin, and Luteolin, respectively. (omitted)

• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.62-66
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• 2007

Ethanol extract from Salvia miltiorrhiza (SME) was tested for breast cancer chemoprevention and metastasis by measuring the activites of cytochrome P45O 1A1, aromatase, ornithine decarboxylase (ODC), and matrix metalloproteinase (MMP)-9. SME significantly inhibited cytochrome P45O 1A1-mediated ethoxyresorufin O-deethylase (EROD) activity in a dose-dependent manner in a concentration range of 100${\sim}$l,200 ${\mu}g/ml$ (p<0.01). Microsomal aromatase (estrogen synthase) activity was suppressed 54.9%${\sim}$77.5% by the SME at concentration of 600${\sim}$l,200 ${\mu}g/ml$. ODC activity induced by 12-O-tet-radecanoylphorbol-13-acetate (TPA) was significantly reduced by the SME 900 and 1,200 ${\mu}g/ml$ (p<0.05) in MCF-7 breast cancer cells. In addition, SME (900 and 1,200 ${\mu}g/ml$) markedly inhibited MMP-9 activity, a key role in cancer metastasis. Therefore, SME is worth further investigation with respect to breast cancer chemoprevention or therapy.

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1114-1121
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• 2005

Flavonoids are polyphenols composed of two aromatic rings (A, B) and a heterocyclic ring (C). In order to determine the effects of the number of hydroxyl groups in the B-ring of the flavonoids on human cytochrome P450 (CYP) 1 family enzymes, we evaluated the inhibition of CYP1A-dependent 7-ethoxyresorufin O-deethylation activity by chrysin, apigenin and luteolin, using bacterial membranes that co-express human CYP1A1, CYP1A2, or CYP1B1 with human NADPH-cytochrome P450 reductase. Chrysin, which possesses no hydroxyl groups in its B-ring, exhibited the most pronounced inhibitory effects on CYP1A2-dependent EROD activity, followed by apigenin and luteolin. On the contrary, CYP1A1-mediated EROD activity was most potently inhibited by luteolin, which is characterized by two hydroxyl groups in its B-ring, followed by apigenin and chrysin. However, all of the 5,7-dihydroxyflavones were determined to similarly inhibit CYP1B1 activity. Chrysin, apigenin, and luteolin exhibited a mixed-type mode of inhibition with regard to CYP1A2, CYP1B1, and CYP1A1, with apparent Ki values of 2.4, 0.5, and 2.0 ${\mu}M$, respectively. These findings suggested that the number of hydroxyl groups in the B-ring of 5,7-dihydroxyflavone might have some influence on the degree to which CYP1A enzymes were inhibited, but not on the degree to which CYP1B1 enzymes were inhibited.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.69-77
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• 2012

To evaluate the effect of endocrine disruption chemicals (EDCs) to aquatic organisms, muddy loach (Misgurnus anguillicaudatus) was exposed to low concentration methomyl for 21 days in order to identify the effect of biomarkers and endocrine. Vitellogenin (VTG) in blood plasma, which used widely as validated biomarker for endocrine disruption, was significantly greater in male fish exposed to 0.4 mg/L and 2 mg/L methomyl, and in female fish exposed to 0.08 mg/L, 0.4 mg/L, and 2 mg/L methomyl for 21 days (p<0.05). This results suggest that methomyl have probability of endocrine disruption to organism on aquatic system. While inhibition of Acetylcholinesterase (AChE) activity and increase of DNA damage in comet assay were verified by fish exposed to methomyl, change of ethoxyresorufin-O-deethylase (EROD) activity was not occurred, comparing the control group (p<0.05). Indicators at the level of organism such as condition factor (CF), hepato-somatic index (HSI), and gonado-somatic index (GSI) were not influenced by exposure of methomyl. In conclusion, these results showed the possibility of methomyl in regard to not only endocrine disruption but also impacts on biochemical biomarkers to aquatic organisms.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.62-68
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• 2012

This study evaluated the screening level assessment of ecological health using four biomarkers and four bioindicators of Misgurnus anguillicaudatus as a indicator species in agricultural area of South Korea during May-June 2011. The endocrine disrupting chemical (EDC) indicators, such as vitellogenin (VTG) and gonado-somatic index (GSI), were not significantly changed in the agricultural site (p>0.05), indicating no effects. The biomarkers and bioindicators were compared between two sites of reference site (RS) and the agricultural site (AS) for screening assessment of ecological health. The ethoxyresorufin-O-deethylase (EROD) activity, acetylcholinesterase (AChE) activity, and DNA damage were significantly changed in the AS compared with the RS (p<0.05). But the individual level bioindicators such as condition factor (CF), hepato-somatic index (HSI), and gonado-somatic index (GSI) were not significantly different from reference site (RS). These results may indicate impairments of ecological health by toxic chemicals and environmental conditions. Current this study is based on screening assessment of biochemical and individual level biomarkers and bioindicators, so further study is required additional biomarkers and population or community level bioindicators for more specific health assessments in agricultural areas.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.446-452
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• 2016

Pharmacokinetic interaction of chrysin, a flavone present in honey, propolis and herbs, with caffeine was investigated in male Sprague-Dawley rats. Because chrysin inhibited CYP1A-selective ethoxyresorufin O-deethylase and methoxyresorufin O-demethylase activities in enriched rat liver microsomes, the pharmacokinetics of caffeine, a CYP 1A substrate, was studied following an intragastric administration with 100 mg/kg chrysin. In addition to the oral bioavailability of chrysin, its phase 2 metabolites, chrysin sulfate and chrysin glucuronide, were determined in rat plasma. As results, the pharmacokinetic parameters for caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) were not changed following chrysin treatment in vivo, despite of its inhibitory effect on CYP 1A in vitro. The bioavailability of chrysin was found to be almost zero, because chrysin was rapidly metabolized to its sulfate and glucuronide conjugates in rats. Taken together, it was concluded that the little interaction of chrysin with caffeine might be resulted from the rapid metabolism of chrysin to its phase 2 metabolites which would not have inhibitory effects on CYP enzymes responsible for caffeine metabolism.

• Journal of Sasang Constitution and Immune Medicine
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• v.17 no.2
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• pp.64-73
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• 2005

1. Objectives The purpose of this study was to investigate the effects of the enzyme activity of Palmulgunja-tang with administered orally solution on cytochrome P450 isozyme 2. Methods This study was carried on through following methods. We treated the rat with the {3-naphthoflavone (${\beta}NF$) of 80mg/kg for 3 days i.p injection. Firstable, microsomal protein was separated and total intracellular protein test was done. Then GOT and GPT were measured and assay of cytochrome P450 IAI/2 enzyme activity was performed according to the method of EROD and MROD. (Ethoxyresorufin-O-deethylase(EROD) activity was used to measure cytochrome P450 lAI activity and methoxyresorufin O-demethylase(MROD) activity was used to measure cytochrome P450 lA2 activity. ) 3. Results and Conclusions 1) PGT recovered the liver damage on ${\beta}NF$ inducible CYP IAI/2 by pre-post and high-low condition. 2) At concentration of post-treated 50mg!kg of PGT, the inhibiting of $\betaNF$ metabolites to liver of rat cytochrome P450 lAl was inhibited by 53.0% respectively. 3) PGT showed 36.0% inhibition of ${\beta}NF$-induced lA2 activity at the concentration post-treated 50mg/kg.