• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1062-1068
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• 2004

Leptin has a major role in the regulation of food intake and energy homeostasis. In addition, leptin participates in many physiological functions including regulation of lipid metabolism. Bovine recombinant leptin protein was produced in E. coli cells in order to understand function of leptin in the regulation of lipid metabolism. The leptin expression vector was constructed in pGEX-4T-3 vector and transformed into E. coli BL21 cells. Expression of the GST-leptin fusion protein was induced with IPTG. The fusion protein was purified using glutathione sepharose 4B batch method, and the recombinant leptin was eluted after thrombin protease digestion. The effect of leptin on glucose transport was examined in the differentiated adipocytes of 3T3-L1 cells. Leptin had no effect on basal and insulin-stimulated glucose transport in 3T3-L1 cells (p>0.05). Effect of recombinant leptin on glucose and acetate transport was examined in adipose tissues of Korean cattle (Hanwoo). Insulin stimulated glucose transport in both intramuscular and subcutaneous adipose tissues (p<0.05), but leptin did not affect glucose transport in both adipose tissues (p>0.05). Insulin stimulated acetate transport in bovine adipose tissues (p<0.05), but leptin did not affect acetate transport (p>0.05). Northern and RT-PCR analyses showed that mRNA levels of uncoupling protein-2 were increased by leptin treatment in 3T3-L1 cells without statistical difference (p>0.05). In conclusion, bovine recombinant leptin did not affect glucose and acetate transport in both 3T3-L1 adipocytes and bovine adipose tissues, while it stimulates UCP-2 mRNA expression in 3T3-L1 cells.

• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.186-192
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• 1991

It is very important to have a good kinetic model which considers the effects of both ammonium and glucose for the control and optimization of the poly-${\beta}$-hydroxybutyrate (PHB) fermentation. A kinetic model for the growth of Alcaligenes eutrophus and the biosynthesis of PHB under both ammonium and glucose limitation was proposed. Growth rate of residual biomass was expressed as a function of concentrations of residual biomass, glucose and ammonium having glucose inhibition. PHB production rate was expressed as a function of concentrations of residual biomass, glucose, ammonium and PHB content having ammonium and product inhibitions. Novel approaches were made to estimate the parameters in the model equations which considered two limiting substrates. Model parameters were evaluated by graphical and simplex methods. The proposed kinetic model fitted the data very well.

• Journal of Community Nutrition
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• v.8 no.4
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• pp.207-213
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• 2006

The present study was conducted to investigate the effect of oolong tea extract on blood glucose level and antioxidant system in diabetic rats. The Sprague-Dawley rats were fed on AIN-76 based experimental diets containing 1 % oolong tea extract for 6 weeks. They were induced to be diabetic by receiving streptozotocin (45mg/kg BW) intramuscularly. Blood glucose, blood and hepatic concentration of vitamins A and E, and antioxidant enzyme activities were measured. Oolong tea extract feeding decreased the plasma glucose in diabetic rats. Dietary supplementation of oolong tea extract did not affect antioxidative enzyme activities such as superoxide dismutase, glutathione peroxidase and catalase in diabetic rats. The plasma level of retinol was increased in diabetic rats by feeding oolong tea extract. Plasma and hepatic levels of ${\alpha}$-tocopherol were higher in diabetic rats fed oolong tea extract. In conclusion, these results suggest that oolong tea extract consumption might reduce the plasma glucose in diabetic rats and protect the oxidative damage from diabetic stress to some extent.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1210-1214
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• 2002

The large and rapid changes of glucose utilization in lactating mammary tissue in response to changes in nutritional state must be largely related by external signal of insulin. This also must be related with the quantity and composition of the diet in vivo. To characterize the mode of gut extract protein with insulin, in vitro experiment was conducted with HC11 cells. The gut extract protein has not only the same effect as insulin alone but also the synergistic effect with insulin in 2-Deoxy[3H] glucose uptake. Although the gut extract did not modulates glucose uptake via increasing the rate of translation of the GLUT1 protein, northern blot analysis indicated that the gut extract protein increased the expression of GLUT1 mRNA by a threefold and also there was a dose-dependent increase in the expression of GLUT1 mRNA. The gut extract protein is therefore shown to be capable of modulating glucose uptake by transcription level with insulin in HC 11 cells.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.359-364
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• 1990

The present study was performed to evaluate the hypoglycemic mechanism of brazilin. Brazilin significantly reduced plasma glucose level in streptozotocin induced diabetie rats and this effect seems to be mediated by extrapancratic effects rather than by pacreatic effect because no significant changes were observed in plasma insulin levels. The rates of glycogen synthesis, glycolysis and glucose oxidation in soleus muscle were markedly increased following brazilin treatment to diabetic animals. Glucose transport seemed to be increased by the treatment of brazilin. Brazilin did not affect insulin binding to muscles from streptozotiocin induced diabetic rats. These results suggest that potentiation of periopheral glucose utilization may be one of the major causes of hypoglucemic action of brazilin.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.2
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• pp.109-111
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• 1998

The effect of dissolved oxygen concentration on the metabolism of glucose in Pseudomonas putida BM014 was investigated. Glucose was completely converted to 2-ketogluconate via extracellular oxidative pathway and then taken up for cell growth under the condition of sufficient dissolved oxygen concentration. On the other hand, oxygen limitation below dissolved oxygen tension (DOT) value of 20% of air saturation caused the shift of glucose metabolism from the extracellular oxidative pathway to the intracellular phosphorylative pathway. Specific activities of hexokinase and gluconate kinase in intracellular phosphorylation pathway decreased as the DOT increased, while 2-ketogluconokinase activity in extracellular oxidative pathway increased under the same condition. This result can be usefully applied to microbial transformation of glucose to 2-ketogluconate, the synthetic precursor for iso-vitamine C, with almost 100% yield via extracellular oxidation by simple DOT control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.277-281
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• 1988

Effect of itaconate upon citrate and isocitrate production of Saccharomycopsis lipolytica were investigated. The percent inhibition of isocitrate lyase activity was about 80% at 0.8 mM itaconate concentration, with Ki value of 0.17 mM in the cleavage reaction. Inhibitory effect of itaconate at 20 mM on S. lipolytica growth was significant on n-hexadecane medium, whereas almost no inhibitory effect on glucose medium. Increasing itaconate concentration in n-hexadecane medium improved isocitrate production up to 80% but no difference was found in glucose medium.

• The Journal of the Korean life insurance medical association
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• v.30 no.2
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• pp.16-19
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• 2011

In patents with diabetes, the higher the serum glucose level was, the more cardiovascular events and death were observed. But with a certain kind of group, to control glucose level tightly does not decrease the incidence of these events. Several studies show that intensive glucose control does not gain benefit in patient with long standing, uncontrolled diabetes, especially having previous cardiovascular events, while definitely preventing progression of newly onset of diabetic nephropathy. Whether intensive glucose control increases mortality in high risk group is obscure and needs more studies with longer observation time.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.222-223
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• 1989

• Korean Journal of Adult Nursing
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• v.18 no.5
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• pp.809-818
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• 2006

Purpose: The purpose of this study was to evaluate the effect of antioxidant vitamins and magnesium supplementation on fasting blood glucose and lipids in patients with type 2 diabetes. Methods: This study is a unequivalent control group pretest-posttest design. Seventyone subjects with type 2 diabetes who were recruited from home visiting clients of a public health center, completed the trial. The experimental group entered a 12-week treatment period with antioxidant vitamins and magnesium and the control group with no antioxidant vitamins and magnesium. Results: Serum level of fasting blood glucose decreased from $134.7mg/d{\ell}$ to $125.0mg/d{\ell}$ and total-cholesterol decreased from $215.5mg/d{\ell}$ to $198.2mg/d{\ell}$ in the experimental group. No changes in fasting blood glucose and total-cholesterol were demonstrated in the control group. Conclusions: A short-term supplementation with antioxidant vitamins and magnesium can reduce fasting blood glucose and total-cholesterol in patients with type 2 diabetes. The continuous effect of this supplementation and the beneficial effect on the prevention of diabetes complication still needs to be demonstrated.