• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4245-4250
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• 2014

Emerging evidence has suggested that glycolysis is enhanced in cancer-associated fibroblasts (CAF), and miR-186 is downregulated during the CAF formation. However, it is not clear whether miR-186 is involved in the regulation of glycolysis and what the role of miR-186 plays during the CAF formation. In this study, quantitative PCR analysises show miR-186 is downregulated during the CAF formation. Moreover, miR-186 targets the 3' UTR of Glut1, and its overexpression results in the degradation of Glut1 mRNA, which eventually reduces the level of Glut1 protein. On the other hand, knockdown of miR-186 increased the expression of Glut1. Both time course and dose response experiments also demonstrated that the protein and mRNA levels of Glut1 increase during CAF formation, according to Western blot and quantitative PCR analyses, respectively. Most importantly, besides the regulation on cell cycle progression, miR-186 regulates glucose uptake and lactate production which is mediated by Glut1. These observations suggest that miR-186 plays important roles in glycolysis regulation as well as cell cycle checkpoint activation.

• 생명과학회지
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• 제17권6호통권86호
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• pp.859-866
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• 2007

본 연구는 임신횐쥐에서 운동이 혈중 인슐린과 렙틴 농도, 그리고 골격근의 GLUT-4와 VAMP-2단백질 발현에 변화를 조사하기 위하여 수행되었다. 본 연구에서 비임신 횐쥐에 비해 임신 횐쥐에서 혈중 인슐린 농도가 유의하게 증가되었고, 렙틴 농도는 유의하게 감소하는 것으로 나타났다. 임신횐쥐에게 달리기 운동을 적용한 결과 임신으로 증가된 인슐린 농도를 유의하게 감소시키면서 렙틴 농도의 감소를 억제시키는 것으로 나타났다. 골격근에서 GLUT-4와 VAMP-2 단백질 발현량을 조사한 결과 비임신 횐쥐에 비해 임신 횐쥐에서 이러한 단백질 발현이 유의하게 감소되었지만, 임신 중 달리기운동을 경험한 횐쥐에서 GLUT-4와 VAMP-2 발현 모두 유의하게 증가되는 것으로 나타났다. 이와 잘이 임신으로 인한 혈중 인슐린 및 렙틴의 변화가 골격근에서 당을 근조직으로 흡수하는 신호 전달 경로와 수송체의 발현 손상과 연관되어있음을 보여주는 것이다. 하지만 임신 횐쥐에서 달리기 운동은 인슐린과 렙틴 농도의 변화를 완화시킴으로써 골격근의GLUT-4와 VAMP-2발현을 유의하게 증가시키는 것으로 나타났다.

• The Korean Journal of Physiology
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• 제25권2호
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• pp.115-123
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• 1991

Molecular association of glucose transporters with the other proteins in the plasma membrane was assessed by gel electrophoresis and immunoblot techniques. Approximately $31.5{\pm}5.1%$ of GLUT-4, $64.8{\pm}2.7%$ of clathrin, 48.7% of total protein in the plasma membrane (PM) were found insoluble upon extraction with 1% Tx-100. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the Tx-100 insoluble PM fraction contained about 4 major polypeptides with apparent molecular weight of above 200, 100-120, 80 and 30-35 KDa that were readily removed upon wash with a high pH buffer which is known to remove clathrin and 0.5 M Tris-buffer which is known to remove assembly proteins (AP). Immunoblotting of GLUT4 and clathrin against specific antibodies showed that GLUT-4 and clathrin were co-solubilized up to 84.6% and 82.7% respectively by wash with a high pH buffer and 1% Tx-100. When the membrane was pre-washed with a high pH buffer and 0.5 M Tris solution, GLUT4 and clathrin were not solubilized further suggesting that GLUT4 molecules are in molecular association with clathrin, AP and/or other extrinsic membrane proteins in plasma membrane and the formation of clathrin-coated structures might be involved in insulin stimulated glucose transporter translocation mechanism.

• 생약학회지
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• 제39권3호
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• pp.228-232
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• 2008

Antidiabetic effects of an aqueous and solvent extract prepared from the root, stem and fruit parts of Acanthopanax senticosus, were investigated in experimental Streptozotocin (STZ)-induced diabetic rats model. The n-butanol and water extracts of A. senticosus were orally administrated once a day for 6 days. The n-butanol extracts of fruit (FB) showed highest efficiency than other groups (water extracts of stem, root and fruit; butanol extracts of stem, root) on serum glucose values in the STZ-induced diabetic rats. We have studied gene expression of glucose transporter genes in C2C12 skeletal muscle cell line during differentiation treated by the n-butanol and water extracts of A. senticosus, SW, RW, FW, SB, RB and FB. The GLUT4 gene was high expressed by FB treatment. These findings suggest that FB of A. senticosus have GLUT4 gene expression activity for glucose homeostasis and may have beneficial effects on blood glucose lowering in the diabetic patients.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.450-455
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• 2004

A reducing glucose-carrying polymer, called poly [3-O-(4'-vinylbenzyl)-D-glucose］(PVG), was interacted with HepG2 cells including a type-l glucose transporter (GLUT-1) on the cell membrane. The cooperative interaction between a number of GLUT-1s and a number of reducing 3-O-methyl-D-glucose moieties on the PVG polymer chain was found to be responsible for the increase in the interaction with HepG2 cells. The affinity between the cells and the PVG was studied using RITC-labeled glycopolymers. The specific interaction between the GLUT-1 on HepG2 cells and the PVG polymer carrying reducing glucose moieties was suppressed by the inhibitors, phloretin, phloridzin, and cytochalasin B. Direct observation by confocal laser microscopy with the use of RITC-labeled PVG and pretreatment of HepG2 cells with the inhibitors demonstrated that the cells interacted with the soluble form of the PVG polymer via GLUT-1, while fluorescence labeling of the cell surface was prevented after pretreatment with the inhibitors of GLUT-1.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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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.

• Journal of Nutrition and Health
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• 제47권3호
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• pp.167-175
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• 2014

본 연구에는 SCLE를 이용하여 시도된 바가 없는 glucose uptake 유도 실험을 수행하여 HepG2 세포에서 포도당흡수가 증가함을 확인하였다. 또한 이런 포도당의 흡수는 HNF-$1{\alpha}$라는 transcription factor의 활성화를 통해 GLUT-2의 발현을 증가시키기 때문인 것을 실험적으로 증명하였다. 뿐만 아니라 Bacillus stearothermophilus 유래의 GK를 이용하여 활성을 측정한 결과 SCLE가 직접적으로 GK를 활성화하여 포도당의 인산화에 영향을 주는 것을 확인할 수 있었으며 그 실험결과들은 Fig. 8에서 도식화 하였다. 본 연구를 통해 SCLE가 ${\alpha}$-glucosidase inhibition 활성에 의한 혈당의 개선과 당뇨예방 효과뿐만 아니라 다양한 세포내 기전을 통해 혈당 및 당뇨의 개선을 유도할 수 있음을 확인하였고, 이는 SCLE가 neutraceuticals 소재로서의 개발가치가 높음을 시사한다.

• 운동영양학회지
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• 제13권2호
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• pp.131-140
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• 2009

The aim of this study was to investigate the expression of PPAR-α, -β/δ, -γ, PGC-1α, GLUT-4 and p-AMPK-α₂ protein in the skeletal muscle of diabetic induced-rats by endurance training combined with rosiglitazone. The expression of PPAR-α, -β/δ, -γ, PGC-1α, GLUT-4 and p-AMPK-α₂ protein in red and white gastrocnemius by western blotting. The body weight was higher in diabetic induced-rats compared to the normal rats and after the treatment of exercise combined with rosiglitazone was significantly reduced in the all group. The levels of blood glucose was higher in diabetic induced-rats compared to the normal rats and after the treatment of exercise combined with rosiglitazone was significantly reduced in the all group. The expression of PPAR-α, -γ, PGC-1α in skeletal muscle of diabetic induced-rats were increased all groups and increased significantly in the group with exercise combined with rosiglitazone. The expression of GLUT-4 and p-AMPK-α₂ protein in the skeletal muscle of diabetic induced-rats were increased all groups and increased significantly in the group with exercise combined with rosiglitazoneI. These results suggest that exercise training and rosiglitazone may act as complementary therapies for the treatment of insulin rasistance.

• BMB Reports
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• 제30권4호
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• pp.240-245
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• 1997

Interactions between ganglioside $G_{M3}$ and glucose transporter, GLUT1 were studied by measuring the effect of $G_{M3}$ on steady-state and time-resolved fluorescence of purified GLUT1 in synthetic lipids and on the 3-O-methylglucose uptake by human erythrocytes. The intrinsic tryptophan fluorescence showed a GLUT 1 emission maximum of 335 nm, and increased in the presence of $G_{M3}$ by 12% without shifting the emission maximum, The fluorescence lifetimes of intrinsic tryptophan on GLUT1 consisted of a long component of 7.8 ns and a short component of 2,3 ns and $G_{M3}$ increased both lifetime components. Lifetime components were quenched by acrylamide and KI. Acrylarnide-mduced quenching of long-lifetime components was partly recovered by $G_{M3}$ However. KI-induccd quenching of short- and long-lifetime components was not rescued by $G_{M3}$. The anisotropy of 1.6-diphenyl-1.3.5-hexatriene (DPH)-probed dimyristoylphosphatidylcholine (DMPC) model membrane was also increased with $G_{M3}$ incorporation, The transport rate of 3-O-methylglucose increased by 20% with $G_{M3}$ incorporation on the erythrocytes, Therefore, $G_{M3}$ altered the environment of lipid membrane and induced the conformational change of GLUT1.

• 약학회지
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• 제42권6호
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• pp.589-597
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• 1998

Effects of Mori Folium Ethanol Soluble Fraction (MFESF) on mRNA expression of glucose transporters, acetyl-CoA carboxylase (ACC) and leptin were examined in db/db mice. 500 and 1000mg/kg dose for MFESF (designated by SY 500 and SY 1000, respectively) and 5mg/kg dose for acarbose were administered for 6 weeks. Quantitations of glucose transporters (GLUT-2 and GLUT-4), ACC and leptin mRNA were performed by RT-PCR and in vitro transcription with co-amplification of rat ${\beta}$-actin gene as an internal standard. Muscular GLUT-4 mRNA expression in MFESF-treated groups were increased dose dependently. On the other hand, MFESF caused the GLLT-4 and leptin mRNA expressions in adipose tissue to decrease dose dependently, which means that triglyceride synthesis in adipocytes might be decreased and consequently signals adipocytes to inhibit the synthesis and release of leptin. Hepatic ACC mRNA expression in MFESF-treated groups was also decreased. and this may result in lowering of serum triiglyceride level. In contrast, liver GLUT-2 mRNA expressions in MFESF-treated and acarbose groups were increased. Higher rate of glucose uptake into hepatocytes is known to inhibit a phosphoenolpyruvate carboxykinase (PEPCK)-catalyzed reaction, which is a rate-limiting step in gluconeogenesis.