• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.114-122
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• 1998

This study was designed to observe the effect of hot water soluble polysaccharides extract(PS) from Lentinus edodes on the enzyme activities related with hepatic function and peroxidation in the rats fed better yellow. The four groups of male SD rats were fed with the diets contained 15% casein(basal diet; NO group), added butter yellow(BO group) or /and PS(NP, BP group) for 6 weeks. The activities of ${\gamma}$-GTP and GPT in BP were significantly lower compared with BO. The activities of glutathione peroxidase, catalase and lactate dehydrogenase were not significantly different between NP and NO, while those activities were significantly lower value in BP than BO. The activities of glutathione S-transferase of the microsomal and cytosol fractions were significantly lower in BP than in BO. The contents of glutathione and malondialdehyde in the liver were considerably low value in BP. In a view of these results the PS of Lentinus edodes prevents the lipid peroxidation and diminishes the liver toxicity caused with better yellow. The superoxide dismutase activity in cytosolic fraction of liver was not found any effect in all groups. But hepatic function enzyme activities such as catalase and glutathione peroxidase, LDH activities were remarkably decreased in the groups 2(basal diet + PS) and the ${\gamma}$-GTP, GOT and GPT activities, too. In liver, the contents of glutathione decreased by PS supplementation but HDL-cholesterol and total cholesterol ratio in plasma decreased at the groups 3, 4. The ${\gamma}$-GTP, GOT and GPT in plasma were remarkably higher in the rats fed the p-DAB than the control group, too. But above enzyme activities significantly decreased in the groups fed PS.

• Journal of Life Science
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• v.9 no.4
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• pp.466-472
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• 1999

These studies were designed to investigate the effects of pine (Pinus densiflora Sieb et Zucc.) needle extract (PNE) on oxygen radicals and their scavenger enzymes in liver membranes of Sprague-Dawley (SD) rats as a study on investigation of anti-aging effect and determination of chemical structures of PNE through the animal experiments. Male SD rats were fed basic diets (control group) and experimental diets (0.5% and 1.0%-PNE group) for 6 weeks. There were no significant differences in hydroxyl radical (·OH) formations of liver mitochondria and microsomes in 0.5%-PNE group, while ·OH formations were significantly decreased (10% and 18%, respectively) in liver mitochondria and microsomes of 1.0%-PNE group compared with control group. Microsomal hydrogen peroxides and cytosolic superoxide radicals were remarkably decreased (20% and 20∼25%, respectively) in 0.5% and 1.0%-PNE groups compared with control group. Mn-SOD activities in mitochondria were significantly increased about 10% in 1.0%-PNE group, while Mn-SOD activities in mocrosomes were remarkably increased (16∼20%) in 0.5% and 1.0%-PNE groups compared with control group. There were no significant differences in Cu, Zn-SOD activities of liver cytosol in 0.5% and 1.0%-PNE groups, while glutathione peroxidase (GSHPx) and catalase (CAT) activities were significantly decreased (28∼30% and 15∼30%, respectively) in liver cytosols of 0.5% and 1.0%-PNE groups compared with control group. These results suggest that these PNE may play a effective role in a attenuating a oxygen radical formations and increasing a scavenger enzyme activities.

• Journal of Nutrition and Health
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• v.28 no.8
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• pp.737-748
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• 1995

Osteoblast(OBL) cells were isolated from ICR Swiss neonatal mouse calvarial tissues and cultured in a CO2 incubator with minimum essential medium (MEM) containing 0.25g BSA. The cells were cultured for 7 days and were treated with bovine parathyroid hormone (bPTH, 1-34) and calcitonin(CT). Enzyme activities related to mineral metabolism and other biochemical actions within the bone cells including protein phosphorylation were investigated. In other experiments using cultured calvarial bone tissues, hormones were treated for 24, 48, 72 or 96 hours. The activities of $\beta$-glucuronidase enzymes involved in bone collagen synthesis and mineral deposits were increased by 8% with bPTH and were inhibited with CT treatment, while those were 67% increase treated with bPTH and CT together. On the other hand, alkaline phophatase(AP) activities were inhibited by PTH hormone at all the time courses observed. Protein phosphorylation reaction in OBL was mediated by bPTH, cAMP and ionized Ca. Phosphorylation was observed in different cell fractions including homogenate, membrane and cytosol. The number of proteins phosphorylated by PTH, cAMP, and Ca were 10, 5, and 9, respectively. Most of the protein kinases(PKs) were existed in cytosolic compartment. In membrane fractions, two bPTH-dependent-PKs (70K, 50K Da) were observed of which 70K Da protein was also Ca-dependent. Most of the cAMP-dependent PKs were regulated via bPTH. 70K, 50K, 5K, 19K, 16K, 10.5K phosphoproteins regulated by Ca share the same pathways as those by bPTH-dependent proteins. Ca seems to regulate PK activities differently from cAMP.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.97-103
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• 1998

Effects of safener fluxofenim was investigated for crop injury of acetanilide's upland herbicides and for enzyme activity of glutathione S-transferase (GST) in grain sorghum. Bioassay with etiolated grain sorghum [Sorghum bicolor (L.) Moench. cv. 'G522DR'] seedlings grown in agar containing metolachlor or alachlor showed that they are strong inhibitors on root growth of grain sorghum ($GI_{50}=4.5{\mu}M$ for metolachlor and $6.2{\mu}M$ for alachlor). The safener fluxofenim applied by seed soaking protected growth of grain sorghum from crop injury of metolachlor or alachlor at the concentrations of 1 to 10 ${\mu}M$. There was a significant increase in glutathione-herbicide conjugates in root tissues of fluxofenim-treated seedlings. Activities of $GST_{-metolachlor}$ and $GST_{-CDNB}$ were increased by 82% and 70%, respectively, in the cytosolic fraction of roots with fluxofenim treatment.

• Nutritional Sciences
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• v.3 no.1
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• pp.25-30
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• 2000

To study the effect of prosomillet (Panicum milaceum) on lipid metabolism, male Sprague-Dawley rats weighing 190$\pm$8g were fed six experimental diets for four weeks. The six diets based on AIN-76 composition consisted of one cholesterol-free(normal) and five 1%(w/w) cholesterol diets, i.e. control, two diets containing additional 0.3 and 0.6%(w/w) methanol extracts of prosomillet and another two diets containing 15 and 30% (w/w) prosomillet powder. There was no difference in weight gains between the groups but relative liver weights increased under the cholestrol diets. Plasma levels of total cholesterol and triglyceride(TG) decreased by 23-27% and by 37-52%, respectively, in the four prosomillet diet groups compared to those of the normal and control groups. Whereas in the liver, only TG levels decreased in the prosomillet diet groups. Fecal excretions of bile acid and cholesterol significantly with methanol extracts of prosomillet. There was a significant increase in the activity of hepatic microsomal cholesterol 7$\alpha$-hydroxylase when feeding 1% cholesterol but prosomillet in the diet, either as in the form of powder or methanol extract, appeared to have only slight additional effects, namely increases in enzyme activity. The activity of liver cytosolic glucose-6-phophate dehydrogenase (G6PDH) tended to be reduced with high cholesterol diets and dropped markedly by 15% using additional prosomillet powder. Those of the liver cytoxolic malic enzyme had a similar tendency to those of G6PDH. The results indicate that certain active components in prosmillet other than fiber have the potential to exert hypolipidemic effects via regulating cholesterol excretions and lipogenesis.

• Biomedical Science Letters
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• v.10 no.2
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• pp.99-105
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• 2004

Liver and serum rhodanese activities were determined in acute ethanol intoxicated rats with extrahepatic cholestasis induced by common bile duct ligation (CBD) to manifest the biochemical background of alcohol drinking hazard under the hepatobiliary disease. Liver cytosolic and microsomal rhodanese activities and these Vmax values in CBD ligated rats with acute ethanol intoxication were found to be decreased much more than that in CBD ligation alone. However, the difference of Km value on above hepatic enzyme was not found between the experimental groups. On the other hand, serum rhodanese activity in CBD ligated rats with acute ethanol intoxication was greater increased more than that in CBD ligation alone. These results indicate that the biosynthesis of the hepatic rhodanese decreases and the serum rhodanese activity increases in cholestasis combined with acute ethanol intoxication, reflecting damage of aggravated hapatocytic membrane. Accordingly, the resulting data supported the fact that alcoholic drinks were enzymologically harmful to the hepatobiliary disease.

• Biomedical Science Letters
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• v.13 no.2
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• pp.135-140
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• 2007

The possible mechanism of decreased catechol-O-methyltransferase (COMT) activity in cholestatic rat liver was studied. Hepatic and serum COMT activities were determined from the experimental rats with choledocho-caval shunt (CCS). The Michaelis-Menten constants in this hepatic enzyme was also measured. The activities of cytosolic, mitochondrial and mircosomal COMT as well as their $V_{max}$ values were found to be decreased significantly in CCS plus taurocholic acid (TCA) injected group than in the control group, such as CCS alone groups. However, their $K_m$ values in the experimental groups did not vary. Seru4m COMT activity increased slightly in the CCS plus TCA injerted group than in the control group. The above results suggest that TCA represses biosynthesis of the COMT in the liver, The elevated activity of the serum COMT is believed to be caused by the increment of membrane permeability of hepatocytes upon TCA mediated liver cell necrosis.

• Herbal Formula Science
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• v.11 no.2
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• pp.135-146
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• 2003

Objectives : Wolguk-whan has been used as a prescription of natural drug for the treatment of stress digestive system disease. Recently, we reported that Wolguk-whan methnol extract (WGWM) exerted a significant protective effect against oxidative damage to the liver of ICR mice. This study was purposed to investigate the effects of Wolguk-whan water extract (WGWW) on liver injury induced by oxidative stress. Methods : In order to investigate the effects of WGWW on acute liver injury, ICR mice were pretreated with WGWW for 6days, starved for 24hrs, and administerated acetamirtophen(500mg/kg, i.p.). In the liver homogenates, lipid peroxide and glutathione(GSH) levels were measured. In addition, activities of hepatic enzyme, such as catalase, glutathione peroxidase(GSH-Px), glutathione S-transferase(GST) were measured in the hepatic mitochondrial and cytosolic fractions. Results : In vivo administeration of WGWW showed effective inhibition of acetaminophen induced lipid peroxidation, and showed elevations of GSH level, catalase, GSH-Px, GST activities. Conclusions : These results suggested that WGWW might suppress the formation of oxidative metabolites, and prevent acetaminophen induced hepatotoxicity.

• Archives of Pharmacal Research
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• v.20 no.1
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• pp.34-38
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• 1997

Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin, EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were incubated at $37^{\circ}C$ for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin, EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for the treatment of open wound.

• BMB Reports
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• v.48 no.11
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• pp.609-617
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• 2015

NAD(P)H:quinone oxidoreductase (NQO1), an obligatory two-electron reductase, is a ubiquitous cytosolic enzyme that catalyzes the reduction of quinone substrates. The NQO1- mediated two-electron reduction of quinones can be either chemoprotection/detoxification or a chemotherapeutic response, depending on the target quinones. When toxic quinones are reduced by NQO1, they are conjugated with glutathione or glucuronic acid and excreted from the cells. Based on this protective effect of NQO1, the use of dietary compounds to induce the expression of NQO1 has emerged as a promising strategy for cancer prevention. On the other hand, NQO1-mediated two-electron reduction converts certain quinone compounds (such as mitomycin C, E09, RH1 and β-lapachone) to cytotoxic agents, leading to cell death. It has been known that NQO1 is expressed at high levels in numerous human cancers, including breast, colon, cervix, lung, and pancreas, as compared with normal tissues. This implies that tumors can be preferentially damaged relative to normal tissue by cytotoxic quinone drugs. Importantly, NQO1 has been shown to stabilize many proteins, including p53 and p33ING1b, by inhibiting their proteasomal degradation. This review will summarize the biological roles of NQO1 in cancer, with emphasis on recent findings and the potential of NQO1 as a therapeutic target for the cancer therapy.