• Advances in Traditional Medicine
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• v.1 no.1
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• pp.28-36
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• 2000

Effects of hesperetin and naringenin on the concentration of triacylglycerol in the serum and liver were studied in male golden hamster fed with the semipurified diet containing at 1% level of them for 3 weeks. The concentration of triacylglycerol in serum of the naringenin group decreased by 31%, whereas that in liver increased by 37% compared to the control group. The concentration of triacylglycerol in the serum and liver of the hesperetin group was slightly lower than the control group. The activity of microsomal phosphatidate phosphohydrolase in the liver, which is a key enzyme for biosynthesis of triacylglycerol, was significantly inhibited in the hesperetin group, whereas it was not affected in the naringenin group. The effect of hesperetin on phosphatidate phosphohydrolase was also measured in vitro. Hesperetin decreased the activity of phosphatidate phosphohydrolase with a dose-dependent manner. Both naringenin and hesperetin did not statistically affect the daily food consumption, body weight, liver weight, and total cholesterol in the serum. The observation accounts for the hypotriglyceridemic effect of hesperetin in the hyperlipidemic hamster.

• Korean Journal of Pharmacognosy
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• v.13 no.3
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• pp.112-115
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• 1982

Alisol A monoacetate, alisol B monoacetate, alisol C monoacetate and alisol B were isolated from Alismatis Rhizoma, which is a herbal drug used frequently in the oriental prescriptions. Potential liver-protective activities of the isolated alisol compounds were evaluated against $CCl_4-induced$ liver damage. The results obtained from liver microsomal enzyme assay, measurement of serum glutamic pyruvic transaminase (EC 2.6.1.2) and serum triglyceride content indicated that alisol A,B and C monoacetates showed significant liver-protective activities against $CCl_4$ poisoning. Alisol B monoacetate exhibited slightly higher activity than that of alisol B.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1415-1423
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• 2007

Carbon tetrachloride ($CCl_4$)-induced liver injury depends on a toxic agent that has to be metabolized by the liver NAPDH-cytochrome P450 enzyme system to a highly reactive intermediate. Alternations in the activity of cytochrome P450 enzymes affect the susceptibility to hepatic injury from $CCl_4$. In this study, we evaluated the potential protective activity of the traditional Korean medicinal herb, Corni fructus (CF), against an experimental model of hepatotoxicity induced by $CCl_4$. The CF exhibited a hepatoprotective activity against $CCl_4-induced$ liver damage in Sprague-Dawley (SD) rats, as measured by GOT, GPT, ALP and histological observation. The CF also showed significant decrease of malodialdehyde (MDA) and increase of glutathion (GSH), catalase activity in rat liver homogenate. In addition, the expression of CYP2E1, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis, was significantly decreased in the liver of CF treated SD rats. But $CCl_4$ and CF has no significant effect on 1A1 and 3A1 isoform of cytochrome P450. Based on these findings, it is suggested that hepatoprotective effects of CF possibly related to antioxidative effects and regulation of CYP2E1 expression.

• BMB Reports
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• v.32 no.4
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• pp.331-338
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• 1999

Ethanol catabolism is thought to produce metabolic disorders resulting in alcoholic liver disease. To investigate the mutual effects of ethanol catabolism and cholestasis induced by common bile duct ligation on the activities of carboxylesterase, we have determined the enzyme activities in rat hepatic (cytosolic, mitochondrial, and microsomal) preparations as well as in rat serum using ten animal models: normal rats (group 1), sham-operated rats (group 2), common bile duct-ligated rats (group 3), ethanol-intoxicated rats (group 4), sham-operation plus chronic ethanol-intoxicated rats (group 5), common bile duct-ligated plus chronic ethanol-intoxicated rats at 1.5h and 24h (groups 7A and 7B), and duct-ligated and acute ethanol intoxicated rats at 1.5 h and 24 h (groups 8A and 8B). The $K_m$ and $V_{max}$ values of carboxylesterase from these hepatic preparations of cholestatic rat liver combined with chronic ethanol intoxication were also measured by using ethyl valerate as the substrate from the 14th day post-ligation. Carboxylesterase activities of all hepatic preparations and rat serum (group 3) showed significant decreases compared to the activities from the sham-operated control (group 2). Enzyme kinetic parameters indicated that $V_{max}$ of carboxylesterase from all the hepatic preparations in cholestatic rats (group 3) decreased significantly, although the $K_m$ values were about the same as in the sham-operated control (group 2). When cholestasis was combined with chronic ethanol intoxication (group 6), carboxylesterase activities showed further decrease in all the hepatic preparations and serum compared to the control activity (group 5). The $V_{max}$ also decreased significantly, although $K_m$ values did not change. When common bile duct ligation was combined with acute ethanol intoxication (group 8), the enzyme activities in the rat liver and serum showed significant decrease compared to the activity from acute ethanol-intoxicated rats (group 7). However, quite contrary to this, the activities of serum from acute ethanol intoxication 1.5 h (group 7A) increased significantly compared to the activities in the normal control (group 1). These results, therefore, suggest that the biosynthesis of hepatic carboxyl-esterase seems to decrease when cholestasis is combined with chronic and acute ethanol intoxication, and the decrease in activity is more significant than from cholestasis alone.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.599-603
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• 2003

This study investigated the effects of Houttuynia Cordata thunb(HCT) administration on the biochemical parameters of function in liver of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) treated rats. Houttuynia Cordata thunb (200mg/kg) was administeres into rats intraperitoneally for four weeks , seven days after the injection of TCDD(1$\mu\textrm{g}$/kg). We examined the antioxidative enzymatic activity by measuring the level of AST, ALT , SOD and Catalase in serum and liver tissue of rats. HCT group showed 49% of inhibitive effect in AST activity compared to TANO group. ALT level of HCT group was decreased to the level of NO group. SOD and Catalase in TANO group were lower than in NO group, but SOD and Catalase in HCT group were increased by 46％ and by 50％ respectively compared to TANO group.

• Mass Spectrometry Letters
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• v.4 no.2
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• pp.34-37
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• 2013

Honokiol and magnolol, the major bioactive neolignans of magnolia officinalis, are the most important constituents of the crude drug prescriptions that are used in the therapy of neuroses and various nervous disorders. There have been limited reports on the effects of neolignoid compounds on human cytochrome P450 activity. Therefore, the inhibitory effects of honokiol and magnolol on seven human cytochrome P450 s were evaluated in human liver microsomes. Honokiol and magnolol showed the most potent inhibition of CYP1A2-mediated phenacetin O-deethylase activity ($IC_{50}$ values of 3.5 and 5.4 mM, respectively) among the seven P450s tested. These in vitro data indicate that neolignan compounds can inhibit the activity of CYP1A2 and suggest that these compounds should be examined for potential pharmacokinetic drug interactions in vivo.

• Journal of Environmental Health Sciences
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• v.19 no.3
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• pp.58-63
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• 1993

In order to elucidate the alteration of drug-metabolizing enzymes and mechanism in the animal with hepatic injury and ketosis, the regulation of P450IIE was studied in the rats with heaptic injury caused by CCl$_4$ and with ketosis caused by streptozotocin and high-fat diet. P450IIE expression in liver was examined by the combination of enzyme activities, Western immunoblot, and mRNA Northern blot analyses using specific polyclonal antibody and cDNA probe for P450IIE. Enzyme activity and amounts of immunoreactive P450IIE were rapidly decreased in a time-dependent manner after a single dose of CCl$_4$ . However, the decreases in P450IIE enzyme activity and immunoreactive protein by CCl$_4$ were not accompanied by a decline in its mRNA level. The data thus suggested a post-translational reduction of P450IIE by CCl$_4$. The enzyme activities (aniline hydroxylase) in hepatic microsomes were elevated about 2-3-fold by streptozotocin and feeding with a high fat diet. This increases in enzyme activities were also accompanied by 3-fold increases in immunoreactive P450IIE protein and its mRNA. Our data thus indicated that P450IIE induction during the ketosis appears to be due to pretranslational activation.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.638-639
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• 2000

Quinone reductase was purified to electrophoretic homogeneity from bovine liver by using ammonium sulfate fractionation, ion-exchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The optimum pH of the enzyme was pH 8.5, and the activity of the enzyme was greatly inhibited by $Cu^{2+}$ and $Hg^{2+}$ ions, dicumarol and cibacron blue 3GA. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene or 4-nitroso-N,N-dimethylaniline. The apparent $K_m$ for 1,4-benzoquinone, azobenzene, and 4-nitroso-N,N-dimethylaniline was 1.64mM, 0.524mM and 0.225mM, respectively. The reduction of azobenzene or 4-nitroso-N,N-dimethylaniline by quinone reductase was strongly inhibited by dicumarol or cibacron blue 3GA, potent inhibitors of quinone reductase.

• Environmental Analysis Health and Toxicology
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• v.7 no.1_2
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• pp.45-51
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• 1992

This study was performed to investigate the effect of Angelicae gigantis Radix extract oil the hepatic detoxifying enzyme activities and lipids. Male sprague-dawley rats were administrated the extracts with benzo(a)pyrene, a hepatotoxic agent, inducing liver damages. Results obtained from this study were as follows: 1. The markedly increased enzyme activities (AST, ALT, LDH, ALP, ${\gamma}$-GTP, GSH-Px) in B(a)P induced groups tended to be decreased by the treatment of the Angelicae gigantis Radix extract. 2. Liver GSH content and lipid peroxide activity were decreased by the administration of the extracts. 3. It tended that the curative effects were better than the protective effects of the extracts.

• Toxicological Research
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• v.13 no.3
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• pp.183-186
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• 1997

Acute toxicity of pectenotoxin 2 (PTX2) was examined in mice. Treatment of mice with a toxic dose of PTX2 resulted in clinical signs such as ataxia, cyanosis and an abrupt decrease in body temperature. Histopathological studies revealed that the liver is the major target organ for PTX2. Activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and sorbitol dehydrogenase (SDH) were significantly elevated by PTX2 administration. Glucose-6-phosphatase activities were not changed by the treatment. The PTX2 treatment decreased relative liver weight without changing the body weight. The effect of PTX2 on hepatic drug metabolizing enzyme system was determined. An ip dose of PTX2 (200 $\mu$g/kg) induced a significant decrease in the hepatic microsomal protein content. Cytochrome P-450 content, cytochrome b$_5$ content, NADPH cytochrome c reductase, aminopyrine N-demethylase activities, or hepatic glutathione content were not altered by PTX2 treatment.