• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.568-578
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• 2001

Background : Lung cancer is frequently cited as an example of a disease caused solely by exposure to environmental carcinogens. However, there is a growing realization that the genetic constitution is also important in determining individual's susceptibility to lung cancer. This genetic susceptibility may result from functional polymorphims of the genes involved in carcinogen metabolism. In this study, the association between GSTM1 and CYP1A1 polymorphisms and the lung cancer risk in Korean males was investigated. Materials and Method : The study population consisted of 153 male lung cancer patients and 143 healthy male controls. The GSTM1 and CYP1A1 genotypes were determined by multiplex PCR and PCR-RFLP analysis. Result : There were no significant differences in the frequency of the GSTM1 null genotype between the cases and the controls. When the cases were categorized by their histologic type, the frequency of the GSTM1 null genotype in the small cell carcinoma group was higher than those of the controls(67.2% vs 55.9%), but the difference was not statistically significant(OR=1.772 ; 95% CI=0.723-4.340). The distribution of the CYP1A1 MspI genotypes among the cases were similar to those among the controls. When the cases were grouped by their histologic type, the ml/m1, ml/m2, m2/m2 genotypes frequencies among the small cell carcinomas(23.0%, 38.5%, and 38.5%, respectively) were significantly different from those of the controls(36.4%, 46.2%, and 7.4%, respectively, p<0.05). When the m1/m1 genotype was used as a reference, the ml/m2 and m2/m2 genotypes were associated with an increased risk for small cell lung cancer(ml/m2 genotype : OR=1.337, 95% CI=0.453-3.947 ; m2/m2 genotype : OR=3.374, 95% CI=1.092-10.421). Conclusion : These results suggest that the GSTM1 and CYP1A1 genotypes may be a genetic determinant of the risk for lung cancer, particlulary small cell carcinoma. Further investigation is needed to confirm these results.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.1
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• pp.49-54
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• 2011

In order to develop the methods for exposure assessment and find susceptibility markers for the workers who are exposed to low doses of toluene, xylene and other chemical in petroleum industries, we investigated the application of P-450 expression in human lymphocytes utilizing mouse monoclonal anti-rat CYP2B1/2, the levels of toluene and xylene in air and their metabolite levels in urine with the levels of expressed CYP2B1/2 proteins. The general characteristics such as age, smoking and drinking habit were no significant difference between the control and exposed workers, but the working durations and working hours were significantly different. Workers in exposed group were exposed to the mean of 2.1 ppm (range, 0.00-4.54) of toluene and 0.3 ppm (rang, 0.00-1.23) of xylene. The mean concentration of urinary hippuric acid was low and less than 1/5 of the biological exposure index recommended by the Ministry of Employment and Labor Korea. Methyl hippuric acid in urine was not detected in control and exposed workers. Also, there were no significant differences in the levels of the urinary metabolites between the control and exposed group. When chemiluminescence dot blottings were carried out utilizing mouse monoclonal antibody against CYP2B1/2, the strong density dots corresponding to a mouse monoclonal antibody was observed in the human lymphocytes from the exposed workers. These results suggested that the chemiluminescence dot blot assay for CYP of lymphocytes should be valuable for identifying CYP expression as biomarkers in the workers exposed to toluene and xylene.

• Journal of Society of Preventive Korean Medicine
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• v.12 no.3
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• pp.99-113
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• 2008

In this study, the author experimented the influence of five herbal medicines, which are Lonicera japonica Thunb, Paeonia suffruticosa Andr., Fraxinus rhynchophylla Hance, Gardenia jasminoides Ellis, Scutellaria baicalensis George which are called 'Chungyulyak(淸熱藥)' on drug metabolizing enzyme cytochrome P450 3A4 in Human Liver Microsome. Above all, the reason for this study is that herbal medicines can be assumed that herbs might have interactions with drugs, other herbs, alcohol and chemicals whether those are much better synergy effects than expected effects when the medicine was treated alone or not. As a result, we showed that all of five traditional herbal medicines had no CYP 3A4 inhibition effect on 10, 20, 30, 40, $50{\mu}g/m{\ell}$ doses in Human Liver Microsome. However, this result are mostly not enough to prove that PMT has a CYP 3A4 inhibition effect. Moreover, it is not that those rates showed that those herbal medicines have CYP 3A4 induction effect. In conclusion, the result could support that those herbal medicines are more safe than chemical drugs even if this is the basic step to prove that result. Therefore, more specific studies to support this result, which are Kinetic study, cell and animal study then finally until clinical research, are required.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.134-142
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• 2020

This study aimed to determine whether there was a difference in lung functions of smokers according to the presence of carcinogenic genetic-metabolizing enzymes by comparing the results of lung functions and the presence of genetic metabolizing enzymes that metabolize tobacco substances. To achieve this, 31 smokers without no illness and no psychiatric history were selected (28 males and 3 females); they were aged 20 to 27 years and were physically and mentally healthy students attending K University. Their lung functions were measured, and gene polymorphisms of cytochrome P-450 1A1 (CYP1A1) related to metabolic activation of tobacco components and gene polymorphism of tumor protein 53 (TP53) related to lung cancer were analyzed. As a result, the mean values of lung function of TT and Arg / Arg without genetic mutations were the highest, and ANOVA analysis of CYP1A1 and lung functions showed that the P-value of FVC was 0.049, which was different between groups. In other words, there is no high mutation in Cytochrome P-450 1A1 (CYP1A1) gene, which is associated with the metabolic activation of tobacco components. In other words, In the absence of the mutant Cytochrome P-450 1A1 (CYP1A1) gene, which is associated with the metabolic activation of tobacco components, the value of FVC was high.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.253.1-253.1
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• 2002

DA-8159 is a new PDEV inhibitor, synthesized by Dong-A Pharm, as an oral agent to treat male erectile dysfunction. DA-8159 and sildenafil are mainly metabolized by cytochrome P450 enzyme CYP 3A4. In this study. we compared the metabolism of DA-8159 with sildenafil in vitro and in vivo. First, we quantified the remaining gatio of original compound, DA-8159 and sidenafil., after we incubated drugs for 30 minutes with human liver microsome cytochrome P 450 3A4. (omitted)

• Journal of Pharmaceutical Investigation
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• v.37 no.2
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• pp.107-111
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• 2007

Epigallocatechin gallate (EGCC), a flavonoid, is the main component of green tea extracts. EGCG has been reported to be an inhibitor of P-glycoprotein (P-gp) and cytochrom P450 3A(CYP3A4). This study investigated the effect of long-term administration of EGCG on the pharmacokinetics of verapamil in rats. Pharmacokinetic parameters of verapamil were determined after oral administration of verapamil (9 mg/kg) in rats pretreated with EGCG (7.5 mg/hg) for 3 and 9 days. Compared to oral control group, the presence of EGCG significantly (p<0.01) increased the area under the plasma concentration-time curve (AUC) of verapamil by 102% (coad), 83.2% (3 days) and 52.3% (9 days), and the peak concentration $(C_{max})$ by 134% (coad), 120% (3 days) and 66.1% (9 days). The absolute bioavailability (A.B.%) of verapamil was significantly (p<0.01) higher by 8.4% (coad), 7.7% (3 days), 6.4% (9 days) compared to control (4.2%), and presence of EGCG was no significant change in the terminal half-life $(t_{1/2})$ and the time to reach the peak concentration $(T_{max})$ of verapamil. Our results indicate that EGCG significantly enhanced oral bioavailability of verapamil in rats, implying that presence of EGCG could be effective to inhibit the CYP3A4-mediated metabolism and P-gp efflux of verapamil in the intestine. Drug interactions should be considered in the clinical setting when verapamil is coadministrated with EGCG or EGCG-containing dietary.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.325-335
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• 2008

The protective effects of the Naringin, on carbon tetrachloride ($CCl_4$)-induced hepatotoxicity and the possible mechanisms involved in this protection were investigated in mice. Pretreatment with Naringin prior to the administration of $CCl_4$ significantly prevented an increase in serum alanine, aspartate aminotransferase activity and hepatic lipid peroxidation in a dose-dependent manner. In addition, pretreatment with Naringin also significantly prevented the depletion of glutathione (GSH) content in the livers of $CCl_4$-induced mice. However, reduced hepatic glutathione levels was unaffected by treatment with Naringin alone. In addition, Naringin prevented $CCl_4$-induced apoptosis and necrosis, as indicated by a liver DNA laddering. To determine whether caspase-8,-3 pathway involved in $CCl_4$-induced acute liver injury, caspase-8, -3 activities were tested by ELISA. Naringin attenuated $CCl_4$induced caspase-8, -3 activities in mouse livers. $CCl_4$-induced hepatotoxicity was also prevented, as indicated by a liver histopathologic study. The effects of Naringin on the cytochrome P450 (CYP) 2E1, the major isozyme involved in $CCl_4$ were also investigated. Treatment of mice with Naringin resulted in a significant decrease of the CYP2E1-dependent hydroxyl at ion and aniline in a dose-dependent manner. These findings suggest that protective effects of Naringin against the $CCl_4$-induced hepatotoxicity may be due to its ability to block CYP2E1-mediated $CCl_4$ bioactivation and that is also protects against caspase-8, -3 pathway mediated apoptosis.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.112-112
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• 2001

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that activates the aryl hydrocarbon receptor (AhR) and disrupts multiple endocrine signaling pathways by enhancing ligand metabolism, altering hormone synthesis, down regulating receptor levels, and interfering with gene transcription. And TCDD-mediated gene transactivation via the AhR has been shown to be dependent upon estrogen receptor (ER) expression in human breast cancer cells. In the present study, we have examined the effect of natural estrogen, phytoestrognes and environmental estrogens on the regulation of CYP1A1 gene expression in MCF-7 human breast cancer cell line. that ER and AhR are co-expressed. pCYP1A1 -luc reporter gene was transiently transfected into MCF-7 cells. These cells were treated with various chemicals and then luciferase assay was carried out. 17be1a-estradiol significantly inhibited TCDD stimulated luciferase activity dose dependently and this inhibition was partially recovered by concomitant treatment of tamoxifen. 17beta-estradiol metabolites, 2-hydroxyestradiol and 16alpha-estriol resulted in less potent inhibitory effect than estradiol and synthetic estrogen, diethylstilbestrol (DES) showed no effect on CYP1A1 gene expression. This study demonstrated that estrogen down-regulated TCDD stimulated CYP1A1 expression via ER mediation. And we have found out that several flavonoids such as genistein, kaempferol, daidzein, naringenin, and alkylphenols such as nonylphenol, 4-octylphenol and resveratrol also inhibited TCDD induced CYP1A1 expression like estrogen.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.469-475
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• 2005

The purpose of this study was to investigate the effect of a cotreatment of bamboo concentrates (Jukcho solution; 0.75, 1.5, and 3.0 mL/kg) with the chemotherapeutic agent paclitaxel on the bioavailability of orally administered paclitaxel (50 mg/kg) in rats. The effect of a pretreatment of bamboo concentrates (1.5 and 3.0 mL/kg for 1.0 h or a consecutive 3 day) was also examined. The paclitaxel plasma concentrations of rats orally administered paclitaxel plus bamboo concentrates (coadministration, 3.0 mL/kg and pretreatment, 1.5 and 3.0 mL/kg) were significantly higher than those of rats treated with paclitaxel alone. Plasma concentrations of paclitaxel in groups pretreated with bamboo concentrates for 3 day were markedly higher than those of a paclitaxel control group at the measured time points. The areas under plasma concentration-time curves (AUCs) of paclitaxel in groups pretreated with bamboo concentrates were elevated and the absolute bioavailability ($AB\%$) and relative bioavailability ($RB\%$) of paclitaxel were also significantly higher than those in the control group. The peak concentration ($C_{max}$), half-life ($t_{1/2}$), and the elimination rate constant ($K_{el}$) of paclitaxel after 3 day of pretreatment with bamboo concentrates were also significantly higher than those in the control, but the time required to reach the maximum plasma concentration ($T_{max}$) of paclitaxel was unaffected by the bamooo concentrates. Western blot analyses demonstrated that the level of CYP3A4 was increased in the livers of rats treated orally with paclitaxel, but this was reversed by pretreating with bamboo concentrates. These results show that bamboo concentrates enhance the bioavailability of orally administered paclitaxel and this effect may be associated with a diminished expression of CYP3A4 in the liver.

• Journal of Pharmaceutical Investigation
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• v.36 no.4
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• pp.263-269
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• 2006

Deficiencies in the early ADMET(absorption, distribution, metabolism, elimination and toxicity) information on drug candidate extract a significant economic penalty on pharmaceutical firms. Microscale cell culture analogue-microscale gastrointestinal(${\mu}CCA-{\mu}GI$) device using Caco 2, L2 and HEp G2/C3A cells, which mimic metabolic process after absorption occurring in humans was used to investigate the toxicity of the model chemical, acetaminophen(AAP). The toxicity of acetaminophen determined after induction of CYP 1A1/2 in Caco 2 cells was not significant. In a coculture system, although no significant reduction in viability of HEp G2/C3A and L2 cells was found, approximately 5 fold increase in the CYP 1A1/2 activity was observed. These results appear to be related to organ-organ interaction. The oral administration of a drug requires addition of the absorption process through small intestine to the current ${\mu}CCA$ device. Therefore, a perfusion coculture system was employed for the evaluation of the absolution across the small intestine and resulting toxicity in the liver and lung. This system give comprehensive and physiologic information on oral uptake and resulting toxicity as in the body. The current ${\mu}CCA$ device can be used to demonstrate the toxic effect due to organ to organ interaction after oral administration,