• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.203-208
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• 1991

The present study was undertaken in order to elucidate the effects of pretreatment with nicotinamide on changes in the hepatic metabolizing enzyme system inducted by streptozotocin (STZ). In rats, STZ(50mg/kg) administered by tail vein caused a significant rise in hepatic aniline hydroxylase and a decrease in aminopyrine N-demethylase when compared to control (p<0.05). Pretreatment with nicotinamice inhibited these effects (p<0.05). Similarly, STZ induced changes in hepatic microsomal cytochrome P-450 activity were inhibited by pretreatment with nicotinamide (p<0.05). However, changes in UDP-glucuronyl transferase and sulfortransferase activity were not significantly different(p>0.05). Pretreatment with nicotinamide also prevented STZ induced increases in glutathion S-tranferase activity when compared to the control(p<0.05). There results suggest that nicotinamide pretreatment suppresses STZ-induced changes in the hepatic metabolizing enzyme system.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.185-192
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• 1990

The present work was undertaken to investigate the protective effect of diallyl disulfide on the bromobenzene toxicity in mice. It was observed that the aniline hydroxylase and epoxide hydrolase activities were not changed by the treatment of diallyl disulfide for 5 days. But glutathione S-transferase activity was significantly increased. A striking enhancement of serum alanine aminotransferase activity and hepatic lipid peroxide content after bromobenzene administration was markedly decreased by diallyl disulfide pretreatment. These results indicate that the inducing effects of diallyl disulfide on the bromobenzene intermediate detoxifying enzyme such as glutathione S-transferase are believed to be a possible protective mechanism for the bromobenzene toxicity in mice.

• Korean Journal of Medicinal Crop Science
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• v.15 no.1
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• pp.21-25
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• 2007

The root of Rosa rugosa has been used in folkloric medicine as a treatment agent for diabetes. In the present study, we investigated whether (+)-catechin isolated from this plant can change the activities of hepatic drug metabolizing enzymes in rats treated with bromobenzene. Pretreatment with (+)-catechin gave no effects on the activities of aminopyrine N-demethylase and aniline hydroxylase, enzymes forming toxic bromobenzene epoxide intermediates and glutathione Stransferase, an enzyme removing toxic epoxides. However, the activity of epoxide hydrolase, an enzyme detoxifying the bromobenzene toxic intermediates was mildly recovered by (+)-catechin treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.976-980
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• 1996

To elucidate the effect of acute ethanol pretreatment on some toluene metabolizing enzyme activities, rats were divided into 4groups: control, alcohol-treated, toluene-treated, rat's and toluene-treated rats pretreated with ethanol. The alcohol or toluene-treated rats showed the significantly increased activities of hepatic aniline hydroxylase(AH) and aminopyrine demethylase(AD) compared to the control group. And the toluene-treated rats pretreated with ethanol showed somewhat decreased tendency of these enzyme activities compared to only toluene-treated rats. Liver benzylalcohol or aldehyde dehydrogenase activities were higher in alcohol or toluene-treated rats than those of the control group. The toluene-treated rats showed the decreased tendency of benzylalcohol dehydrogenase activities by the pretreatment of alcohol. Furthermore, toluene treated-rats showed the markedly decreased activity of benzaldehyde dehydrogenase by the ethanol pretreat-ment. On the other hand, hepatic xanthine oxidase activity in toluene-treated animals pretreated with ethanol was significantly higher than those of the toluene alone-treated rats. These results indicate that the combination of ethanol with toluene treatment for a short period of time possibly results in decreased activity of some toluene metabolizing enzymes in rats.

• Archives of Pharmacal Research
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• v.18 no.3
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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.

• Natural Product Sciences
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• v.8 no.1
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• pp.18-22
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• 2002

Inhibitory effects of the essential oils obtained from ten herbs were tested on acetaminophen-induced lipid peroxidation in the rat. The oil of Artemisia princeps var. orientalis buds (AP-oil) showed the most significant hepatic malondialdehyde value which was comparable to those of ascorbic acid and methionine. This was warranted by the protective effect on hepatic glutathione depletion. Overview of the data on the activities of hepatic microsomal enzymes, aminopyrine N-demethylase and aniline hydroxylase led to the notice that the suppressed activities of those enzymes are mainly responsible for the anti-lipid peroxidation. The interpretation of GC-MS data on the AP-oil revealed the ingredient of cineol, thujone, carvone, borneol, camphor and terpineol.

• Biomedical Science Letters
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• v.9 no.2
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• pp.93-98
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• 2003

To investigate the cyclohexane and xylene mixture treatment on the liver damage, the rats were treated by the mixture of cyclohexane and xylene (CH＋X) and then, liver damage was demonstrated by liver function findings based on liver weight/body weight, serum level of alanine aminotransferase (ALT), xanthine oxidase (XO) and then compared with cyclohexane treated group (CH group) and xylene-treated group (X). The CH＋X group showed merely severer liver damge than CH or X group. On the other hand, CH＋X group showed lower activity of hepatic cytochrome P-450 dependent aniline hydroxylase (CYPdAH) than CH or X group, but no statical differences were demonstrated among three experimental groups. Especially the hepatic GSH content was merely declined than CH or X group and the activity of hepatic GST was higher in CH＋X group than CH or X group. In conclusion, cyclohexane and xylene mixture treated animals showed merely severer liver damage than cyclohexane or xylene treated group and such a fact may be caused by inhibition of cyclohexane or xylene metabolism and oxygen free radical.

• Natural Product Sciences
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• v.18 no.2
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• pp.121-129
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• 2012

Hepatoprotective effects of methanol extract and alisol B 23-acetate of Alisma orientale were studied in acetaminophen (APAP)-treated rats. APAP increased hepatic content of lipid peroxide, which was suppressed by methanol extract and alisol B 23-acetate. The liver of rats treated with APAP had higher P-450, aminopyrine N-demethylase and aniline hydroxylase activities than those of normal control rats. The increases in hepatic drug metabolizing enzymes by the i.p. injection of APAP were significantly alleviated by the administration of methanol extract or alisol B 23-acetate. The injection of APAP also resulted in a substantial reduction of hepatic glutathione content and glutathione S-transferase activity, and the decreases were partially, but significantly, restrained by the oral administration of methanol extract prior to the i.p. injection of APAP. Hepatic activities of glutathione reductase (GR) and ${\gamma}$-glutamylcystein synthetase ${\gamma}$-GCS) were also decreased significantly in APAP-treated rats. The decreases in hepatic GR and ${\gamma}$-GCS activities by APAP injection were improved partially, but significantly, with administration of methanol extract of A. orientale. Treatment with alisol B 23-acetate also improved the hepatic ${\gamma}$-GCS activity significantly, but not GR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.702-708
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• 1993

The study was attempted to elucidate the mechanism of GE-132(100mg/kg, p.o. for 6 weeks) on the metabolism of bromobenzene (460mg/kg, i.p. bid, for 2 days), which has potent carcinogenicity, mutagenicity and hepatotoxicity. It showed that activities of cytochrome p-450, aminopyrine demethylase and aniline hydroxylase, which have epoxide generating property, were not changed by GE-132 treatment. On the other hand, epoxide hydrolase was not changed but that glutathione S-transferase was significantly increased by GE-132 treatment. And also ${\gamma}-glutamylcysteine$ synthetase was not changed following the GE-132 treatment, but the activity of glutathione reductase was significantly increased. The level of hepatic glutathione which was decreased by bromobenzene recovered markedly by GE-132 pretreatment. It is concluded that the mechanism for the observed effect of GE-132 on bromobenzene metabolism is due to the induction of glutathione S-transferase.

• Biomolecules & Therapeutics
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• v.5 no.1
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• pp.59-66
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• 1997

This study was done to determine that vitamins I and C are synergistic in protecting liver cells during hepatic ischemia and repefusion. Rats treated with vitamins I and C were subjected to 60 min of hepatic ischemia and to 1 and 5 hr of reperfusion thereafter. Serum aminotransferase level and microsomal lipid peroxidation were markedly increased by ischemia/reperfusion. These increases were significantly attenuated by vitamins E, C or its combination. Hepatic wet weight-to-dry weight ratio was increased in ischemic group, but this increase was prevented by combination of vitamin I and C. Bile flow and cholate output were markedly decreased by ischemia/reperfusion and vitamin C alone and combination of vitamin I and C restored their secretion. Cytochrome P-450 content and aminopyrine N-demethylase activity were decreased by ischemia/ reperfusion and restored by vitamin C and combination of vitamin I and C to the level of sham-operated rat. Aniline p-hydroxylase activity was increased by ischemia/reperfusion and this increase was prevented by vitamin E. Our findings suggest that ischemia/reperfusion diminishes hepatic secretory and microsomal functions by increasing lipid peroxidation and vitamins I and C synergistically ameliorates these changes.