• Archives of Pharmacal Research
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• 제18권3호
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• pp.179-182
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• 1995

Previous study showed that $CCl_4$ administration evoked a rapid decrease in cytochrome $P_{450}$ 2E1 protein soon after the exposure due to posttranslational inhibition(Biochem. Biophys. Res. Commun. 179:449-454, 1991). In this report, aniline hydroxylase and the amounts of immunoreactive $P_{450}$ 2E1 were rapidly decreased during day 1 to 2 and recovered during day 3 to 4 after a single dose of $CCl_4$. The activity of pentoxyresorufin-O-dealkylase was also suppressed at day 1 and began to repair from day 2. However, the decrease in immunoreactive $P_{450}$ 2C content was not observed. The decreases in $P_{450}$ 2E1 enzyme activity and immunoreactive protein by acute $CCl_4$ treatment were accompanied by a decline in $P_{450}$ 2E1 mRNA level. The data thus suggested a pretranslational reduction of $P_{450}$ 2E1 during day 1 to 2 after acute $CCl_4$ treatment.

• 동의생리병리학회지
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• 제37권2호
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• pp.30-35
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• 2023

Bisphosphonates, estrogen, and calcium supplements are commonly used medications for postmenopausal osteoporosis, but they are associated with various side effects such as vaginal bleeding, deep vein thromembolism, and breast cancer. In this study, we aimed to investigate the potential of a compound isolated from the roots of Oryza sativa L. to improve osteoporosis using an ovariectomized mouse model. We isolated and identified oryzativol A, a lignan compound, through chemical analysis of an ethanol extract using a bioassay-guided fractionation protocol. We also examined the metabolism, clearance, and CYP enzyme activity of oryzativol A, and found that it showed plasma stability of over 80% at all analysis times, and indicating a low likelihood of inactivation or excretion by the CYP3A4 enzyme. Our results showed that the high-dose group of oryzativol A exhibited a significant increase in bone mineral density compared to the control group. Although the ALP concentration did not differ significantly compared to the control group, it showed a tendency to increase in the high-dose group of oryzativol A. Furthermore, the abnormal ratio of serum Ca/P, caused by osteoporosis, was improved to a level closer to that of the normal group as the dosage of oryzativol A increased. Taken together, these findings suggest that oryzativol A is stable in vivo and has potential as a therapeutic agent for osteoporosis, particularly when administered in high doses.

• 동의생리병리학회지
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• 제30권4호
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• pp.279-288
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• 2016

To observe the potential hepatoprotective effects of Gongjin-dan on the acute ethanol (EtOH)-induced liver damages in C57BL/6 mice with its possible action mechanisms. EtOH-mediated acute hepatic damages were induced by oral administration of EtOH total 3 doses. The changes on the body weight, liver weight, albumin, TG, AST, ALP, ALT, hepatic TG contents, hepatic antioxidant defense system, TNF-α, CYP 2E1 activity and mRNA expressions of hepatic lipogenic genes - SREBP-1c, SCD1, ACC1, FAS, PPARγ and DGAT2 or genes involved in fatty acid oxidation - PPARα, ACO and CPT1 were observed with final liver histopathological inspections after 15 days of continuous administration of silymarin 200 mg/kg, Gongjin-dan (GJD) 400, 200 and 100 mg/kg. The results were compared with silymarin 200 mg/kg treated mice. Marked decreases of body and liver weights, increases of serum AST, ALT, Albumin and TG levels, hepatic TG contents, TNF-α level, CYP 2E1 activity and mRNA expressions of hepatic lipogenic genes or decreases mRNA expressions of genes involved in fatty acid oxidation were observed with histopathological changes related hepatosteatosis increases of immunolabelled hepatocytes, as the results of a binge drinking of EtOH in the present study. Also destroys of hepatic antioxidant defense systems were demonstrated in EtOH control mice as compared with intact vehicle control mice, respectively. The results suggest that oral administration of 400, 200 and 100 mg/kg of GJD favorably protected the liver damages from acute mouse EtOH intoxications.

• Environmental Analysis Health and Toxicology
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• 제21권3호
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• pp.291-299
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• 2006

The experiments investigated whether early exposure to testosterone propionate (TP) during prepuberty alters testis development in Sprague-Dawley male rats. We performed Hershberger assay using the stimulated weanling male rats by OECD protocols, cDNA microarray, and Western blot. TP was subcutaneously injected to uncastrated Sprague-Dawley male rat of 22 days old for 10 consecutive days at doses of 0.4, 0.8, 1.0, 1.2, 1.6 mg/kg per day. At necropsy, the following tissues were removed and weighed: combined testes, epididymides (Epi), Cowper's glands (COW), levator am, and bulbocavernosus muscles (LABC), seminal vesicles, together with coagulating gland (SV) and ventral prostate (VP). We found that TP increased the weights of Epi, VP, SV, COW, and LABC, while testis was decreased in a dose-dependent manner. In cDNA microarray analysis of testis, there were significant reductions in the expression of cytochrome P450 11A (CYP11A), the rate-limiting enzyme of steroidogenesis. Taken together these results, TP exposure before puberty in male rats may produce the delay in testis development by inhibiting the CYP11A gene expression.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.111-111
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• 2001

Resveratrol (trans-3,4',5-trihydroxystilbene), which is a polyphenolic compound found in a variety of plants such as grapes and wine, has been reported to have a variety of anti-inflammatory, anti-platelet, and anti-carcinogenic effects. Recently resveratrol of was reported to serve as an estrogen agonist in MCF-7 cells Based on its structural similarity to diethylstilbestrol, a synthetic estrogen, we examined whether resveratrol and its derivatives might be estrogenic using stable MCF-7-ERE cells. Resveratrol functioned as a superagonist at high concentrations (i.e., produced a greater maximal transcriptional response than estradiol) Among the resveratrol derivatives, 10 compounds showed significant estrogenic activity.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.561-565
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• 2018

The late-stage doxorubicin biosynthesis pathway acting enzyme (DoxA) from Streptomyces peucetius CYP129A2 exhibited substrate promiscuity towards the stilbene group of compounds such as resveratrol. DoxA along with two accessory enzymes ferrdoxin reductase and ferredoxin from spinach hydroxylated resveratrol at the 3'-position in vitro to produce piceatannol. The product was identified by HPLC-PDA and high-resolution HR-qTOF-ESI/MS analyses in positive mode. The ESI/MS fragments resembled the hydroxylated product of resveratrol.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.161-161
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• 2001

Resveratrol (trans-3, 4', 5-trihydroxystilbene), which is a polyphenolic compound found in a variety of plants such as grapes and wine, has been reported to have a variety of anti-inflammatory, anti-platelet, and anti-carcinogenic effects. Recently resveratrol was reported to serve as an estrogen agonist in MCF-7 cells Based on its structural similarity to diethylstilbestrol, a synthetic estrogen, we examined whether resveratrol and its derivatives might be estrogenic using stable MCF-7-ERE cells. (omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.185-185
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• 2001

The CD95 (Fas, APO-1) is known to play a key role as a transmembrane cell surface receptor that mediates apoptosis of many cell types through binding with Fas ligand or cross-linking to agonistic anti-Fas antibody. Activation of CD95 provokes a potent and rapid responses in a variety of cell types by unknown mechanism.(omitted)

• Toxicological Research
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• 제20권3호
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• pp.195-203
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• 2004

4-Tert-Octylphenol (OP) is a surfactant additive widely used in the manufacture of a variety of detergents and plastic products. OP can disrupt endocrine function in humans and animals. This study was carried out to obtain toxicokinetic parameters of OP in male Sprague-Dawley (SD) rats. Male rats were administered with OP by single oral application of 200 mg/kg body weight. Blood, urine and tissues samples were taken at several time intervals after administration. Analysis of samples for OP was performed by column-switching high performance liquid chromatography (HPLC). In addition, we exam-ined tissue distribution and accumulation of OP after single oral application of 50, 100, and 200 mg/kg, single intravenous injection of 1, 5 and 10 mg/kg or daily application of 50 mg/kg for 14 consecutive days. After single oral administration of 200 mg/kg, Cmax of 213 $\pm$ 123 ng/ml was reached within the first 1.3 hr (Tmax) in the plasma. AUC was calculated for 1,333$\pm$484 ngㆍhr/ml. The final elimination half-life of plasma was longer than that of urine, but urinary clearance was lower than oral. A very small fraction of OP (Fe < 0.0017%) was excreted in urine within 24 hr. These results indicated that the major excretion route of OP was not urine. The mean maximal tissue distribution of OP was obserbed at 6 hr after treatment and slowly decreased time-dependently. High OP concentrations were detected in fat at 24 hr. The OP in fat was slowly released with longer elimination half-life and lower clearance than that of other tissues. OP was not accumulated in the liver following single oral application but 14-day oral treatments resulted in two-fold accumulation. It was probably due to the saturation of detoxification pathways. On the other hand, the mRNA expression of cytochrome P450 isoforms except CYP2C11 was not affected by OP at any dose. The expression of CYP2C11 mRNA decreased in a dose-dependent manner. This result suggests that OP changes expression of the male-specific cytochrome P450 isoforms in rat liver, and these changes are closely related to the toxic and estrogenic effect of OP.

• 한국환경보건학회지
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• 제26권3호
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• pp.11-17
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• 2000

There are among the most relevant toxic emissions from incinerators such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs). Induction of cytochrome P4501A1 catalyzed 7-ethoxyresorufin O-deethylase(EROD) activity in mammalian cell culture(EROD bioassay) is thought to be a selective and sensitive parameter used for the quantification of dioxin-like components. In this study, the toxic emissions from several school waste incinerators were evaluated by determination of CYPIA catalytic activity and cytotoxicity using cell culture microbioassay. The incinerator residue and soil samples were collected from the schools located in Kyunggi province from April to June 1999. The samples were extracted in a Soxhlet apparatus using toluene for 20 hours. In order to clean-up, concentrated crude extracts were applied to basic alumina column. The EROD activities of extracts in the H4IIE cells were from 1.91$\pm$0.32 ng-TEQ/g to 24.54$\pm$3.48 ng-TEQ/g of biochemical-TEQ value. In soil samples, CYP1A catalytic activity was 0.09~0.64 ng-TEQ/g. EROD bioassay, seems to be a useful short-term bioassay when information about the biological response of complex environmental samples is needed. Although further study is needed, these results indicate that the potent toxic emissions are produced from school waste semi-incinerators.