• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.511-520
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• 2008

Purpose: Diabetes mellitus is a clinically and genetically heterogeneous group of metabolic disorders manifested by abnormally high levels of glucose in the blood. Mounting evidence demonstrates that diabetes is a risk factor for gingivitis and periodontitis. The circulating mononuclear phagocytes in diabetic patients with hyperglycemia are chronically exposed to high level of serum glucose. Thus, this study attempted to determine the effect of pre-exposure of monocytes and macrophages to high concentration of glucose on lipopolysaccharide (LPS)-induced production of pro-inflammatory mediators. Material and Methods: For this purpose, cells were cultured in medium containing normal (5 mM) or high glucose (25 mM) for 4-5 weeks before treatment for 24 h with LPS. LPS was highly purified from Porphyromonas gingivalis or Prevotella intermedia by phenol extraction. Result: Results showed that prolonged pre-exposure of cells to high glucose markedly increased LPS-stimulated NO secretion when compared to normal glucose. In addition to NO, high glucose also augmented LPS-stimulated IL-6, IL-8, and TNF-$\alpha$ secretion after cells were exposed to high glucose for 4 weeks. Conclusion: The present study demonstrates that pre-exposure of mononuclear phagocytes with high glucose augments LPS-stimulated production of pro-inflammatory mediators. These findings may explain why periodontal tissue destruction in diabetic patients is more severe than that in non-diabetic individuals.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.834-837
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• 2002

A fluorescent glucose analogue,2-[N-(7-nitrobenz-2-ox a-1,3-diazol-4-yl) amino] -2- deoxy-D-glucose (2-NBDG), which had previously been developed for the analysis of glucose uptake in living cells, was investigated to determine its biological activity on microorganisms.2-NBDG did not show any inhibitory effect on growth of yeast cells and bacteria. In contrast, 2-NBDG exhibited strong inhibitory effects on filamentous fungal growth. The growth of filamentous fungi was completely inhibited, when 2-NBDG was supplemented as sole carbon source. The inhibitory effect was decreased by the addition of glucose in the test medium. Furthermore, 2-NBDC inhibited chitinase activity of Trichoderma sp. These results suggested that the inhibitory effects of 2-NBDG on filamentous fungi might be partially due to the inhibition of chitinase.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.154-160
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• 1990

Hydroxypropyl methacrylate polymeric membranes having tertiary amine moiety were prepared to control the release rate of insulin in response to the concentration of glucose. Hydroxypropyl methacrylate was copolymerized with N, N'-diethylaminoethylacrylate. Its water content was increased with decreasing the pH of the medium and was reversible with variation of the pH of the medium. The permeation coefficient of insulin through copolymer membrane was also increased with decreasing the pH of the medium. Combining this copolymer membrane and the glucose oxidase immobilized membrane as a sensor for glucose, composite membrane was prepared. The permeability of this composite membrane was increased with addition of glucose.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.674-679
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• 2005

With addition of uracil during fermentation, the production rate of $1,3-{\beta}-glucan(curdlan)$ was enhanced. Since uracil was used as precursor of UDP-Glucose, the UDP-glucose level was increased and further glucan synthesis rate was increased.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.86-87
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• 2007

An amperometric glucose biosensor has been developed using viologen derivatives as electron mediator of glucose oxidase (GOD) at Au electrode. Highly stable self assembled monolayer (SAM) of thiol-based viologen is immobilized onto the Au electrode followed byGOD is immobilized onto the viologen modified electrode. This biosensor response to glucose was evaluated amperometrically in the potential of -300 mV. Upon immobilization of glucose oxidase onto the viologen modified-electrode, the biosensor showed rapid response towards glucose. Experimental conditions influencing the biosensor performance such as, pH, potential were optimized and assessed. This biosensor offered an excellent electrochemical response for glucose concentration below ${\mu}mol$ level with high sensitivity and selectivity and short response time. The levels of the RSD's (< 5 %) for the entire analyses reflected the highly reproducible sensor performance. Using the optimized a linear relationship between current and glucose concentration was obtained up to $4.5{\times}10^{-4}$ M. In addition, this biosensor showed well reproducibility and stability.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.121-126
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• 1990

The contractility of isolated rat atria, suspended in Krebs-Ringer bicarbonate medium containing 5.5mM glucose, was depressed approximately 50% by 0.1 mM of lidocaine. Partial recovery of the lidocaine-depressed contractility was achieved by the metabolizable substrates pyruvate, acetate, and fructose, but not by addition of glucose. Glucose produced the dose-dependent increase in the force of contraction of normal atria, whereas pyruvate, acetate, and fructose produced no significant effect in the contractile activity of the normal atria. In the absence of exogenous glucose lidocaine produced more marked depression of atrial contractility than that in the presence of exogenous glucose. The results of this study may confirm that the utilization of cardiac glycogen is also inhibited by lidocaine at sites of the glucose phosphate isomerase step or step between glycogen to glucose-6-phosphate.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.61-66
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• 1991

In order to improve the productivity of ethanol by sugar-alcohol-tolerant Saccharomyces cerevisiae D1, the effect of addition of soybean meal on the alcohol fermentation was investigated. The addition of soybean meal led tn the increase of the ethanol productivity and viable cell concentration. Increasing the mont of soybean meal increased the number of viable cells and the consumption percentage of glucose. The water-soluble fraction of soybean meal was nearly as effective as whole-soybean meal, whereas the lipidic fraction had no positive effect. The addition of 4% soybean meal increased the rate of ethanol production regardless of the initial concentrations of glucose. The rate of glucose consumption fermenting a soybean meal supplemented medium was higher than possible in a non-supplemented medium, either in the absence or in the presence of ethanol. But the percentage of ethanol inhibition of the glucose consumption rate was identical for supplemented md unsupplemented media. The increase of final ethanol concentration could not be attributed In an increase of ethanol tolerance of yeast cells but to the satisfaction of nutritional deficiencies.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.1
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• pp.77-86
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• 1998

The uptake of glucose for metabolism and growth is essential to most animal cells and is mediated by glucose-transporter (GLUT) proteins. The aim of this study was to determine which class of glucose transporter molecules was responsible for uptake of glucose in the mouse early embryo and at which stage the corresponding genes were expressed. In addition, co-culture system with vero cell was used to investigate the effect of the system on GLUT expression. Two-cell stage embryos were collected from the superovulated ICR female and divided into 3 groups. As a control, embryos were cultured in 0.4% BSA-T6 medium which includes glucose. For the experimental groups, embryos were cultured in either co-culture system with vero cells or glucose-free T6 medium supplemented with 0.4% BSA and pyruvate as an energy substrate. 2-cell to blastocyst stage embryos in those groups were respectively collected into microtubes (50 embryos/tube). Total RNA was extracted and RT-PCR was performed. The products were analysed after staining ethidium bromide by 2% agarose gel electrophoresis. Blastocysts were collected from each group at l20hr after hCG injection. They were fixed in 2.5% glutaraldehyde, stained with hoechst, and mounted for observation. In control, GLUT1 was expressed from 4-cell to blastocyst. GLUT2 and GLUT3 were expressed in morula and blastocyst. GLUT4 was expressed in all stages. When embryos were cultured in glucose-free medium, no significant difference was shown in the expression of GLUT1, 2 and 3, compared to control. However GLUT4 was not expressed until morular stage. When embryos were co-cultured with vero cell, there was no significant difference in the expression of GLUT1, 2, 3 and 4 compared to control. To determine cell growth of embryos, the average cell number of blastocyst was counted. The cell number of co-culture ($93.8{\pm}3.1$, n=35) is significantly higher than that of control and glucose-free group ($76.6{\pm}3.8$, n=35 and $68.2{\pm}4.3$, n=30). This study shows that the GLUT genes are expressed differently according to embryo stage. GLUTs were detectable throughout mouse preimplantation development in control and co-culture groups. However, GLUT4 was not detected from 2- to 8-cell stage but detected from morula stage in glucose-free medium, suggested that GLUT genes are expressed autocrinally in the embryo regardless of the presence of glucose as an energy substrate. In addition, co-culture system can increase the cell count of blastocyst but not improve the expression of GLUT. In conclusion, expression of GLUT is dependent on embryo stage in preimplantation embryo development.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.748-756
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• 2000

Effects of xanthine (X), xanthine oxidase (XO), and catalase (C), $H_2O_2$, and carbohydrates on sperm capacitation, acrosome reaction, and fertilizing ability in vitro were examined. Glucose alone, but not fructose, supported the maximum rate of sperm capacitation and acrosome reaction. However, in the combination of X, XO, and C (XXOC) or $H_2O_2$, fructose alone also supported maximum capacitation, acrosome reaction, and fertilization. Either insufficient or excessive amounts of $H_2O_2$ decreased sperm capacitation and the acrosome reaction. In order to understand how glucose generates $H_2O_2$ or other reactive oxygen species in sperm cells, 6-aminonicotinamide, an inhibitor of the pentose-phosphate pathway (PPP), and apocynin, an inhibitor of NADPH oxidase, were added to sperm suspensions in glucose-containing medium. Results appeared that sperm capacitation, acrosome reaction, and fertilization were consequently inhibited by either one of these compounds. These inhibitory effects were nullified by addition of XXOC. These results support the hypothesis that glucose, in addition to being a substrate for glycolysis, facilitates sperm capacitation and the acrosome reaction by generating reactive oxygen species through G-6-P dehydrogenase and NADPH oxidase.

• Reproductive and Developmental Biology
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• v.33 no.4
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• pp.211-216
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• 2009

A cell frequently utilizes glucose as a fuel of energy and a major substrate of lipid and protein syntheses. A regulation of glucose movement into and out of the cells is precisely controlled by cooperative works of passive and sodium-dependent active processes. At least 13 glucose cotransporter (Slc2a, GLUT) isoforms involve in passive movement of glucose in cells. The efferent ductules (EDs) play in a number of important functions for maintenance of male fertility. In the present study, using real-time PCR analysis, we determined gene expression of five Slc2a isoforms in the EDs. In addition, we compared expression levels of these Slc2a isoforms according to postnatal development ages, 1 week, 2 weeks, 1 month, and 3 months. Results from the current study showed that expression of Slc2a1, Slc2a3, and Slc2a5 mRNAs reached the highest levels at 1 month of age, followed by a transient decrease at 3 months of age. In addition, the level of Slc2a4 mRNA reminded at steady until 1 month of age and was significantly reduced at 3 months of age, whereas the highest level of Slc2a 8 mRNA was detected at 2 weeks of age. Data from the present study indicate a differential expression of various Slc2a isoforms in the ED according to postnatal ages. Thus, it is believed that glucose movement through the epithelial cells in the ED would be regulated by the coordinated manner among Slc2a isoforms expressed at a given age.