• Archives of Pharmacal Research
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• v.11 no.2
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• pp.122-126
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• 1988

The effects of psoralen and angelicin on hepatic microsomal drug-metabolizing enzyme (DME) activities were investigated to elucidate the mode of the interaction of furanocoumarins with DME system. A single administration (30 mg/kg,i. p.) of both coumarins to mice cased a significant prolonagation of hexobarbital-induced hypnosis as well as an increase in strychnine toxicity. The inhibitory potencies of both coumarins as measured by rat hepatic microsomal aminopyrine N-demethylase and hexobarbital hydroxylase activities in vitro were considerably weaker than those of other furanocoumarins which possess a side chain moiety. Both coumarins were found to have significant inducing effects of DME system, with repeated treatments of them. The activities of an angular coumarin were stronger than those of a linear coumarin.

• The Korean Journal of Pharmacology
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• v.18 no.1
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• pp.55-63
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• 1982

Lipid peroxidation is the reaction of oxidative deterioration of polyunsaturated lipids and this peroxidation involves the direct reaction of oxygen and lipid to form free radical intermediates, which can lead to autocatalysis. As results of the extensive studies on the lipid peroxidation by many authors, the relationship between lipid peroxidation and the drug metabolizing system as well as the actions of free radicals on the peroxidation was reasonably well known. For a long time, the mechanism of hepatotoxicity of $CCl_4$ was not clearly understood. However, it is now quite well established that $CCl_4$ is activated in vivo to a free radical which is a highly reactive molecule. Therefore, lipid peroxidation which induces the reduction of cytochrome P-450 and aminopyrine demethylase activity is known as decisive event of $CCl_4$ hepatotoxicity. On the other hand, it was also reported that singlet molecular oxygen produces lipid peroxidation in liver microsomes. In this study the effects of benzoyl peroxide on the lipid peroxidation and drug-metabolizing enzyme were examined. Benzoyl peroxide mixed with starch and phosphates etc. is usually used as a food additive for flour bleaching and maturing purpose because of its oxidative property. Albino rats were used for the experimental animals. Benzoyl peroxide was suspended in soybean oil and sesame oil and administered intraperitoneally or orally. TBA value and aminopyrine demethylase activity were determined in liver microsomal fraction and serum. The results were summerized as following. 1) Body weights of animals administered benzoyl peroxide suspension were decreased while that of oil administered group were increased. 2) The activity of aminopyrine demethylase was generally decreased in animals administered oil suspension of benzoyl peroxide. Furthermore, the marked reduction of the enzyme activity was observed in animals administered benzoyl peroxide intraperitoneally. 3) Generally, microsomal TBA values as well as serum TBA were significantly elevated in benzoyl peroxide group in comparison with the control group. However, the more remarkable increase of serum TBA than microsomal TBA was observed in animals administered orally for 6 days. 4) Specifically, the changing pattern of TBA value was notable in serum rather than in liver microsome by intraperitoneal administration of benzoyl peroxide.

• 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.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.205-205
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• 1996

본 실험은 간장허혈 및 재관류시 야기되는 간장 손상에 대해 vitamin C와 E 각각의 효과와 이들의 병용효과를 알아보고자 하였다. 실험군은 흰쥐에 vitamin E(25mg/kg)를 실험전 3일간 투여한 군, vitamin C(100mg/kg)를 실험 5분전 경정맥주사한 군 및 vitamin C와 E의 병용 투여군등의 3군으로 하여 각각에 허혈을 유발시킨 후 (60분) 재관류 1시간, 5시간에 간세포 손상정도(AI.T, AST, liver wet-weight to dry-weight ratio), 지질과산화(MDA), 담즙분비변동(bile flow, bilirubin, cholate output) 및 약물대사효소계의 변동(cytochrome P$_{450}$, aminopyrine-N-demethylase, aniline p-hydroxylase activity) 등을 관찰하였다. 실험결과로는 허혈 및 재관류로 인한 ALT, AST MDA는 재관류 5시간에 최고치를 이루었으며 이는 vitamin C와 vitamin E의 각각 투여로 억제되었고, 특히 vitamin C와 E의 병용투여로 더욱 현저하게 억제되었다. 간세포 부종의 지표인 liver wet-weight to dry-weight ratio도 vitamin C와 E의 병용투어로 유의성있게 억제되었다. 담즙분비량 및 담즙산량은 vitamin C 투여와 vitamin C와 E 병용투여로 허혈 및 재관류로 감소된 양을 증가시켰고, 특히 vitamin C와 E의 병용투여는 담즙분비량에 있어 현저한 상승을 나타내었다. 허혈 및 재관류로 인한 cytochrome P$_{450}$양의 감소와 aminopyrine N-demethylase 활성의 억제는 vitamin C 투여와 vitamin C와 E의 병용투여에 의해 유의성 있게 증가하였다. 이상의 결과로 보아 vitamin C와 vitamin E는 각각 허혈 및 재관류로 인한 간장손상을 완화시켰으며 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.

• Toxicological Research
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• v.11 no.2
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• pp.247-252
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• 1995

To evaluate the effect of xanthine oxidase on liver injury by $CCl_4$, liver damage was induced both in allopurinol pretreated rats (500 mg/kg. ip) and control group by twice intraperitoneal injection of $CCl_4$ (0.1 ml/100 g body wt. 50% in olive oil) at interval of one day. Increases in the levels of serum alanine aminotransferase and liver weight/body weight (%) by $CCl_4$ were significantly smaller inallopurinol pretreated rats than in control whereas the hepatic microsomal glucose-6-pholphatase activities were significantly higher in allopurinol pretreated rats than control group by $CCl_4$ treatment. These results indicates that allopurinol pretreatment may reduce the liver damage in $CCl_4$ intoxicated rats. In rats either with $CCl_4$or not, hepatic type O xanthine oxidase activities were significantly reduced by allopurinol pretreatment and the increasing rate of these enzymes to each control was remarkably lower in allopurinol pretreated rats than control. Liver cytosolic protein contents and aniline hydroxylase, aminopyrine demethylase activities were higher in allopurinol pretreated rats than coirol rats when animals were treated with $CCl_4$. On the other hand, neither allopurinol pretreated nor $CCl_4$ treatment caused any significant changes in hepatic superoxide dismutase and catalase activities. Hepatic glutathione contents were higher in $CCl_4$-treated rats than control, but no significant changes were found in both between the allopurinol treated rats and $CCl_4$-treated rats pretreated with allopurinol, and glutathione and glutathione S-transferase activities were significantly reduced in $CCl_4$-treated rats than control whereas these enzyme activities showed on significant change in both between allopurinel treated and $CCl_4$-treated rats pretreated with allopurinol. It is concluded that xanthine oxidase reaction system augment $CCl_4$ induced liver injury via even oxygen free radical system.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.185-193
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• 2004

The effects of membrane lipid peroxidation and retinyl palmitate on rat liver microsomal functions were investigated in vitro. Rat liver homogenates exposed to oxygen tension for 0, 3, 6, 9 or12 hours and lipid peroxidation levels were evaluated by the measurements of fluorescence intensity, malondialdehyde (MDA) and retinyl palmitate. The fluorescence intensity of homogenates and microsomes were elevated and retinyl palmitate concentrations were decreased. But the concentration of MDA was not affected to exposure time. Therefore, fluorescence intensity and retinyl palmitate concentration were used to analyze the correlation between lipid peroxidation and microsomal functions. To investigate the liver microsomal functions, the microsome was isolated from rat liver homogenates exposed to oxygen. The concentration of cytochrome P450 and the activity of NADPH-cytochrome P450 reductase in liver microsomes were gradually decreased with increasing the exposure time. The correlation between fluorescence intensity of microsomes showed a very high inverse correlation of -0.97 and -0.93, respectively. The decrease of cytochrome P450 concentration was due to the regeneration of cytochrome P450 to cytochrome P420. Also, the activities of cytochrome P450-dependent aminopyrine demethylase and benzpyrene hydroxylase of liver microsomes were gradually decreased with increasing the exposure time. The correlation with fluorescence intensity of microsome showed a high inverse correlation of -0.97 and -0.91, respectively. The retinyl palmitate concentrations of rat liver homogenates were decreased with increasing the exposure time. The decrease of retinyl palmitate concentration was followed by a low concentration of cytochrome P450 and activity of NADPH-cytochrome P450 reductase. The correlation indicated high direct correlation of 0.92 and 0.93, respectively. The decrease of retinyl palmitate concentration was also accompanied by the reduction of aminopyrine demethylase and benzpyrene hydroxylase activities. The correlation was analyzed a high direct correlation of 0.90 and 0.85, respectively. In conclusion, these studies have shown that the membrane lipid peroxidation of rat liver microsome proportionally decreased microsomal enzyme activities in vitro experiments.

• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.260-264
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• 1999

Korean traditional fermented soy paste (doenjang) prolonged the life span of Balb/c mice injected with the sarcoma-180 cells. The activities of liver enzymes, such as xanthine oxidase, aminopyrine N-demethylase, aniline hydroxylase, ${\gamma}$-glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase (GST), and the contents of lipid peroxide and glutathione were determined from the sarcoma-180 cell injected mice that were treated with methanol extracts from doenjang, miso and soybean. The content of lipid peroxide and the activity of xanthine oxidase in the liver of Balb/c mice which were increased by the transplantation of the sarcoma-180 cells were decreased by treatment with the methanol extract from doenjang. But the activities of aminopyrine N-dementhylase and aniline hydroxylase were not affected by the treatment of methanol extracts from doenjang to the mice injected with the sarcoma-180 cells. The content of glutathione, the activities of glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase decreased by the injection of the sarcoma-180 were recovered considerably by the treatment of the methanol extract from doenjang.

• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.280-285
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• 1997

Pectenotoxin 2 (PTX2), isolated from marine sponges, was examined for its hepatotoxic potential using male ICR mice. PTX2 $(20\;or\;100\;{\mu}g/kg/day,\;ip)$ was administered to mice repeatedly for one or two week. Histopathological examination revealed an increase in granularity in the liver from the mice treated with PTX2. PTX2 did not alter the parameters for hepatotoxicity and nephrotoxicity such as sorbitol dehydrogenase (SDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and blood urea nitrogen (BUN). Cytochrome P-450, cytochrome $b_5$, or NADPH cytochrome c reductase was net changed by repeated administration of PTX2. Hepatic microsomal activity of p-nitroanisole O-demethylase, but not aminopyrine N-demethylase, was slightly depressed by PTX2 administerd repeatedly $(100\;{\mu}g/kg/day,\;ip)$ fur 2 weeks. The toxicity of PTX2 $(200\;{\mu}g/kg/day,\;ip)$ was determined in mice pretreated with a metabolic inducer or inhibitor such as phenobarbital, 3-methyl-cholanthrene, $CoCl_2$, or SKF 525-A. Significant alterations in lethality and hepatotoxicity of PTX2 were observed in mice pretreated with a metabolic modulator. The results suggest that liver seems to be the target organ for PTX2 toxicity and also that induction of the PTX2 toxicity may be associated with hepatic drug metabolizing activity.

• 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.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.240-243
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• 1988

The hexane extract from Nutmeg, the seed of Myristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by $SiO_2$ column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B (II) and dehydrodiisoeugenol (III) were isolated as active principles. Compounds II and III, with a single treatment (200mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they possess CNS-depressant properties.