• Journal of Nutrition and Health
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• v.34 no.5
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• pp.499-512
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• 2001

This study was performed to investigate effects of dried leaf powders, water, 75% and 95% ethanol extracts of persimmon leaf and green tea on lipid metabolism, lipid peroxidation and antioxidative enzyme activity in 12-month-old rats. Fifty-four male Sprague-Dawley rats weighing 542$\pm$4.5g were blocked into groups according to their body weight and were raised for four weeks with the diets containing 5%(w/w) dried leaf powders of persimmon(Diospyros kaki Thunb) and green tea(Camellia Sinensis O. Ktze), water or 75% and 95% ethanol extracts from same amount of each dried tea powder. Food intake was not significantly different among all groups, but weight gain of green tea powder group was significantly lower than that of control group. Plasma and liver lipid levels of all the tea diet groups were lower than those of control group. Especially, 75% ethanol extract of persimmon leaf decreased total lipid and triglyceride concentrations in plasma and 95% ethanol extract of persimmon leaf decreased liver total lipid level. However, there was no difference between 75% ethanol extracts groups and 95% ethanol extracts groups in lipid metabolism. Superoxide dismutase(SOD) and catalase activities in erythrocyte were remarkably increased by all the green tea diets. SOD, catalase and glutathione peroxidase activities in liver were increased by the feeding of ethanol extracts from green tea and persimmon leaf powder. Liver xanthine oxidase activity was not different among all groups. Plasma Thiobarbirutic acid reactive substance(TBARS) concentrations of all the green tea diet groups were significantly low. It was thought that high flavonoids in green tea inhibited plasma lipid peroxidation by promoting SOD, catalase activities in erythrocyte. 95% ethanol extract of persimmon leaf also inhibited plasma lipid peroxidation by high vitamin E and beta-carotene. Persimmon leaf powder decreased liver TBARS concentration by vitamin E, betacarotene and vitamin C and by increasing activities of antioxidative enzymes with flavonoids. In conclusion, dried leaf powders, water, 75% and 95% ethanol extracts of persimmon leaf and green tea were effective in lowering lipid levels and inhibiting lipid peroxidation in 12-month-old rats. Above all, ethanol extracts of persimmon leaf decreased plasma and liver lipid levels and persimmon leaf powder effectively inhibited liver lipid peroxidation. Extracts of green tea leaf inhibited plasma lipid peroxidation. In lowering lipid levels and inhibiting lipid peroxidation, ethanol extracts were more effective than water extracts, but there was no difference between 75% ethanol extracts and 95% ethanol extracts in lipid metabolism. (Korean J Nutrition 34(5) : 499~512, 2001)

• Korean Journal of Community Nutrition
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• v.13 no.2
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• pp.263-275
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• 2008

Impaired fasting glucose (IFG) is one of significant risk factors of developing diabetes. The persons with IFG are, thus, an important target group for primary prevention of diabetes. It is well known that plasma homocysteine concentration may be increased in poor folate nutritional status. Elevated level of plasma homocysteine is considered as a marker of enhanced oxidative stress. In addition, the protective effect against oxidative stress may be diminished in poor antioxidative nutrient status as vitamin C. It is, therefore, important to maintain adequate nutritional status of folate and vitamin C in the patients with type 2 diabetes or IFG. This study was performed to determine the effects of supplementation of folic acid or vitamin C on plasma concentrations of homocysteine, oxidized LDL, and lipids and on the activity of plasma anti-oxidative enzyme in patients with IFG. A total of 97 patients with IFG were participated voluntarily with written consents. They were divided into one of the four experimental groups; Control (C), Folatesupplemented (F), Ascorbate-supplemented (A), and Folate plus ascorbate-supplemented (FA). The subjects in C were taken placebo, those in F were supplemented 1 mg of folate, those in A were received 1,000 mg of vitamin C, and those in FA were given 1 mg of folate plus 1,000 mg of vitamin C daily for 4 weeks. No change in plasma concentrations of vitamin C, lipids, and oxidized LDL and the activity of GSH-Px were observed in vitamin C-supplemented group (A + FA) and folate-supplemented group (F + FA) compared to the placebo group (C + A). Only the folate-supplemented group (F + FA) had significantly increased average serum folate concentration and lowered plasma homocysteine concentration compared to the placebo group (C + A). Thus, it should be recommended the patients with IFG to increase folate intake through diets and, if it is not sufficient, to take folic acid supplements to prevent the development of complications induced by hyperhomocysteinemia as well as oxidative stress.

• BMB Reports
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• v.31 no.3
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• pp.227-232
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• 1998

The leukocyte NADPH oxidase of neutrophils is a membrane-bound enzyme that catalyzes the production of $O_2^-$ from oxygen using NADPH as an electron donor. Dormant in resting neutrophils, the enzyme acquires catalytic activity when the cells are exposed to appropriate stimuli. During activation, the cytosolic oxidase components $p47^{phox}$ and $p67^{phox}$ migrate to the plasma membrane, where they associate with cytochrome $b_{558}$, a membrane-bound flavohemoprotein, to assemble the active oxidase. The oxidase can be activated in a cell-free system; the activating agent usually employed is an anionic amphiphile such as sodium dodecyl sulfate (SDS). Because $p47^{phox}$ can translocate by itself during activation, the conformational change in $p47^{phox}$ may be responsible for the activation of NADPH oxidase. We show here that the treatment of $p47^{phox}$ with SDS leads to an increase in the reactivity of the sutbydryl group of cysteines toward N-ethylmaleimide, indicating that the conformational change occurs when $p47^{phox}$ is exposed to SDS. We propose that this change in conformation results in the appearance of a binding site through which $p47^{phox}$ interacts with cytochrome $b_{558}$during the activation process.

• Natural Product Sciences
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• v.20 no.1
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• pp.65-70
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• 2014

This study was carried out to investigate the potential effects of Gardenia jasminoides (GJ) extracts, on hepatic steatosis and lipid metabolism in mice fed with high-fat diet (HFD). GJ extracts (100 mg/kg, ${\times}10$ weeks) fed mice showed reduced body weight, adipose tissue weight, reduced aminotransferase level in plasma and hepatic lipid (triglyceride, total cholesterol) content. These effects were accompanied by decreased expression of lipogenic genes, sterol regulatory element binding protein-1c (SREBP-1c), liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), cluster of differentiation 36 (CD36), lipoprotein lipase (LPL) and decreased lipogenic enzyme FAS and HMG-CoAR enzyme activities while elevating carnitine palmitoyltrasferase-1 (CPT) activity. Based on these results, we speculated that the inhibitory effect on hepatic steatosis of GJ extract containing geniposide is the result of suppression of lipid synthesis in mice fed with HFD, suggesting that GJ extract may be beneficial in preventing hepatic steatosis.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.1
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• pp.12-22
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• 2013

Objective: We investigated the norepinephrine transporter (NET) expression in normal and pre-eclamptic placentas and analyzed the invasion activity of trophoblastic cells based on norepinephrine (NE)-NET regulation. Methods: NET and NE expression levels were examined by western blot and enzyme-linked immunosorbent assay, respectively. Trophoblast invasion activity, depending on NE-NET regulation, was determined by NET-small interfering RNA (siRNA) and NET transfection into the human extravillous trophoblast cells with or without NE treatment and invasion rates were analyzed by zymography and an invasion assay. Results: NET mRNA was expressed at a low level in pre-eclamptic placentas compared with normal placentas and NE concentration in maternal plasma increased significantly in pre-eclamptic women compared to normal pregnant women (p<0.05). NET gene upregulation and NE treatment stimulated trophoblast cell invasion up to 2.5-fold (p<0.05) by stimulating matrix metalloproteinase-9 activity via the phosphoinositol-3-kinase/AKT signaling pathway, whereas NET-siRNA with NE treatment reduced invasion rates. Conclusion: NET expression is reduced by inadequate regulation of NE levels during placental development. This suggests that a complementary balance between NET and NE regulates trophoblast cell invasion activities during placental development.

• Journal of Plant Biology
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• v.32 no.4
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• pp.265-274
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• 1989

The effect of Ca2+ on auxin-induced ehtylene production in etiolated mungbean (Vigna radiata W.) hypocotyls was studied. Auxin-induced ethylene production by mungbean seedlings which had been germinated in the presence of 5-10mM Ca2+ (High Ca2+ ; HC) is greater than that by seedlings which had been germinated in distilled water (Low Ca2+ ; LC). The effect of Ca2+ on auxin-induced ethylene production was greatly increased after 12hr of incubation period. The stimulation of auxin-induced ethylene production by Ca2+ was specific, since divalent cations, such as Mg2+ and Mn2+ did not enhance auxin-induced ethylene production. Calcium also promoted ethylene evoluation induced by methionine and 1-Aminocyclopropane-1-carboxylic acid(ACC). The effect of Ca2+ on auxin-induced ethylene production was not caused by increase in free IAA or ACC contents of hypocotyl tissue. Dimethyl sulfoxide and Triton X-100, that disrupts the emembranes, inhibited ethylene production to a greater extent in LC segments than in HC segments. Addition of Ca2+ to the incubation medium for LC segments resulted in enchancement of ethylene production probalby because the membrane integrity is supported under these conditions. Comparison of activity of Ethylene Forming Enzyme(EFE) in LC and HC hypocotyl segments indicated that the enzyme activity of HC was about 2 times higher than that of L.C. It is suggested that Ca2+ increases the activity of plasma membrane-bound EFE through its stabilizing effect onn the membrane, which in turn brings about promotion of ethylene production.

• BMB Reports
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• v.48 no.8
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• pp.438-444
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• 2015

Lysosomal storage diseases (LSDs) are a group of inherent diseases characterized by massive accumulation of undigested compounds in lysosomes, which is caused by genetic defects resulting in the deficiency of a lysosomal hydrolase. Currently, enzyme replacement therapy has been successfully used for treatment of 7 LSDs with 10 approved therapeutic enzymes whereas new approaches such as pharmacological chaperones and gene therapy still await evaluation in clinical trials. While therapeutic enzymes for Gaucher disease have N-glycans with terminal mannose residues for targeting to macrophages, the others require N-glycans containing mannose-6-phosphates that are recognized by mannose-6-phosphate receptors on the plasma membrane for cellular uptake and targeting to lysosomes. Due to the fact that efficient lysosomal delivery of therapeutic enzymes is essential for the clearance of accumulated compounds, the suitable glycan structure and its high content are key factors for efficient therapeutic efficacy. Therefore, glycan remodeling strategies to improve lysosomal targeting and tissue distribution have been highlighted. This review describes the glycan structures that are important for lysosomal targeting and provides information on recent glyco-engineering technologies for the development of therapeutic enzymes with improved efficacy. [BMB Reports 2015; 48(8): 438-444]

• BMB Reports
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• v.36 no.2
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• pp.149-153
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• 2003

The dibucaine number (DN) was determined for serum cholinesterase (EC 3.1.1.8, SChE) in plasma samples. The ones with a DN of 79-82 were used, because they had the "usual" SChE variant. The enzyme was assayed colorimetrically by the reaction of 5,5'-dithiobis-[2-nitrobenzoic acid] (DTNB) with the free sulfhydryl groups of thiocholine that were produced by the enzyme reaction with butrylthiocholine (BuTch) or acetylthiocholine (AcTch) substrates, and measured at 412 nm. Dibucaine, a quaternary ammonium compound, inhibited SChE to a minimum within 2 min in a reversible manner. The inhibition was very potent. It had an $IC_{50}$ of $5.3\;{\mu}M$ with BuTch or $3.8\;{\mu}M$ with AcTch. The inhibition was competitive with respect to BuTch with a $K_i$ of $1.3\;{\mu}M$ and a linear-mixed type (competitive/noncompetitive) with respect to AcTch with inhibition constants, $K_i$ and $K_I$ of 0.66 and $2.5\;{\mu}M$, respectively. Dibucaine possesses a butoxy side chain that is similar to the butryl group of BuTch and longer by an ethylene group from AcTch. This may account for the difference in inhibition behavior. It may also suggest the existence of an additional binding site, other than the anionic binding site, and of a hydrophobic nature.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.603-608
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• 1997

To improve animal production, a simple and accurate pregnancy diagnosis plays a very important role. Therefore, the purpose of this study was to develop an on-farm blood progesterone enzyme immunoassay (EIA) system for monitoring the early pregnancy in sows. Star tubes coated with mouse monoclonal anti-progesterone antibody were used for this proposed EIA system which was tested in field trials. The results could be obtained within 30 minutes either by spectrophotometry or the naked eye. Heparinized fresh blood samples collected from the ear vein of sows 17-22 days after breeding (day 0) were tested qualitatively to diagnose sows as pregnant or non-pregnant with high ( > 3 ng/ml) or low ($${{\leq_-}}3ng/ml$$) progesterone in the blood. To provided a double check data, plasma progesterone levels were also measured quantitatively by the same EIA system with some modification. Total agreement of diagnosis by the on-farm EIA kit and by farrowing or abortion from 128 tested sows was found to be 92.2% accuracy (93.1% on pregnant diagnosis and 83.3% on non-pregnant diagnosis). It was concluded that the on-farm EIA blood progesterone test is a very useful method for monitoring the early pregnancy status of sows.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1476-1480
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• 2009

Antioxidant activities of mulberry leaf extracted with different concentrations of EtOH were investigated. Total phenolic content and electron donating abilities of extract from 70% EtOH were the highest. Extracts obtained from EtOH-water mixture were shown to be significantly higher superoxide dismutase (SOD)-like activities than other treatment (p<0.05). Angiotensin-converting enzyme (ACE) inhibition was the greatest at 50% EtOH concentration (p<0.05). The extracts from 30-70% EtOH exhibited higher ferric reducing ability of plasma (FRAP) value than rest of the concentration (p<0.05). In case of nitrite scavenging activity, much higher scavenging activities were observed when the extraction was performed with EtOH or EtOH-water mixture (p<0.05). The results indicate that concentration of EtOH as extraction solvents can affect the antioxidant activity of mulberry leaf, which may provide useful information on the optimal solvent conditions for the extraction.