• BMB Reports
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• v.46 no.12
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• pp.567-574
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• 2013

Liver plays a major role in maintaining glucose homeostasis in mammals. Under fasting conditions, hepatic glucose production is critical as a source of fuel to maintain the basic functions in other tissues, including skeletal muscle, red blood cells, and the brain. Fasting hormones glucagon and cortisol play major roles during the process, in part by activating the transcription of key enzyme genes in the gluconeogenesis such as phosphoenol pyruvate carboxykinase (PEPCK) and glucose 6 phosphatase catalytic subunit (G6Pase). Conversely, gluconeogenic transcription is repressed by pancreatic insulin under feeding conditions, which effectively inhibits transcriptional activator complexes by either promoting post-translational modifications or activating transcriptional inhibitors in the liver, resulting in the reduction of hepatic glucose output. The transcriptional regulatory machineries have been highlighted as targets for type 2 diabetes drugs to control glycemia, so understanding of the complex regulatory mechanisms for transcription circuits for hepatic gluconeogenesis is critical in the potential development of therapeutic tools for the treatment of this disease. In this review, the current understanding regarding the roles of two key transcriptional activators, CREB and FoxO1, in the regulation of hepatic gluconeogenic program is discussed.

• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.215-220
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• 1986

Glucose, trehalose, and glycogen content were measured in haemolymph and the body during larval development of the oriental corn borer, Ostrinia furnacalis ($Guen\'{e}e$). Glucose content varied in haemolymph, but in the body it gradually decreased at all larval stages. As the larva proceeds growth, the initial high level of trehalose increased further in haemolymph whereas the low level trehalose gradually decreased in the body. Glycogen levels in haemolymph rose gradually during larval growth whereas those in the body increased sharply at the two latter instar larval stages. It is apparent that the existence of a homeostasis in carbohydrate levels between haemolymph ana the body.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.159-167
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• 2009

Objectives : So-Dang-Hwan (SDH) is used as a traditional treatment of diabetes in oriental clinics in Korea. This study aimed to evaluate antidiabetic effect of SDH in streptozotocin (STZ)-induced diabetic rats. Methods : Diabetes was induced by i.p. injection of STZ (45 mg/kg) to Sprague-Dawley rats. Experimental animals (eight per group), were treated by oral administration of SDH (60 mg/kg body weight) and glibenclimide (1 mg/kg), a known antidiabetic drug for comparison, during 5 weeks. To veridy the effect of SDH, the levels of glucose, triglyceride, insulin, BUN and creatinine were measured in sera from experimental diabetic rats, and an oral glucose tolerance test (OGTT) was also performed. Results : SDH prevented body weight loss in diabetic rats. SDH exhibited at termination, a significant reduction in blood glucose levels in STZ-induced diabetic rats. SDH significantly reduced serum creatinine levels toward the normal levels. The OGTT results showed a significant improvement in glucose tolerance in rats treated with SDH. Conclusions : These data indicate that SDH treatment may improve glocose homeostasis in STZ-induced diabetes.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3389-3393
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• 2015

Background: Chronic inflammation could affect the occurrence and development of malignant tumors. To explore the levels of tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) and C-reactive protein (CRP) in patients accompanied by impaired glucose tolerance (IGT) and their clinical significance. Materials and Methods: A total of 210 patients hospitalized in Affiliated Hospital of Taishan Medical University from Jun., 2013 to Dec., 2014 were selected, in which 92 cases were accompanied by IGT. Meanwhile, 80 randomly-selected healthy people by physical examination were as the control. The levels of routine biochemical indexes, plasma TNF-${\alpha}$ and CRP in all subjects were measured. Results: Both systolic and diastolic pressures in hypertension group and hypertension plus IGT group were significantly higher than in control group (p<0.01), but there was no statistical significance between these two groups (p>0.05). The levels of fasting plasma glucose (FPG) and blood glucose 2 h after taking glucose in hypertension plus IGT group were markedly higher than other groups (p<0.01). Homeostasis model assessment-insulin resistance (HOMA-IR), TNF-${\alpha}$ and CRP contents were on the progressive increase in control, hypertension and hypertension plus IGT groups, but significant differences were presented among each group (P<0.01). Hypertension accompanied by IGT had a significantly-positive association with CRP, TNF-${\alpha}$, FPG and blood glucose 2h after taking glucose. Conclusions: The levels of plasma TNF-${\alpha}$ and CPR in patients with hypertension accompanied by IGT increase significantly, indicating that inflammatory reaction in these patient increases, thus suggesting that these patients should be focused regarding cancer prevention.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.4
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• pp.374-379
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• 2021

Objective: We aimed to evaluate associations between the ratio of serum estrone (E1) to estradiol (E2) and parameters related to serum glucose metabolism and insulin resistance in women with polycystic ovary syndrome (PCOS). Methods: In total, 133 women between the ages of 18 and 35 diagnosed with PCOS were enrolled in this study. All participants with PCOS underwent blood tests to determine hormonal and biochemical metabolic parameters and a standard 2-hour 75-g oral glucose tolerance test. They were divided into two groups according to the serum E1-to-E2 ratio: group 1 (E1/E2 ratio <2.0) and group 2 (E1/E2 ratio ≥2.0). Results: In the comparative analysis, the waist-to-hip ratio (WHR) was the only clinical variable that was significantly different between the two groups. Patients with a higher E1/E2 ratio showed higher fasting insulin levels, homeostasis model for insulin resistance, and postprandial glucose level at 2 hours (PPG2). In a correlation analysis, only PPG2 was significantly related to the serum E1/E2 ratio. However, after controlling for the confounding effects of body mass index (BMI) and WHR, fasting glucose was also significantly correlated with the serum E1/E2 ratio. Conclusion: Women with PCOS with a higher serum E1/E2 ratio were found to be more likely to show higher fasting insulin and postprandial glucose levels. Significant correlations were found between the serum E1/E2 ratio and both fasting and postprandial serum glucose levels after adjusting for BMI and WHR in women with PCOS.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.3-4
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• 2003

Body weight is maintained at a relatively constant level over days and months despite variability in food intake and physical activity. To achieve energy homeostasis, the hypothalamus receives information related to energy surplus or shortage from the periphery and controls food intake and energy expenditure. Leptin, an adipocyte derived hormone, is a principal mediator that signals the brain about the stored energy status. Increased leptin signaling in the brain prevents excess energy stores by suppressing food intake and increasing energy expenditure. In addition, insulin and nutrients themselves, such as glucose and free fatty acids, also regulate food intake.

• Journal of Yeungnam Medical Science
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• v.40 no.1
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• pp.4-11
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• 2023

Caloric restriction is a popular approach to treat obesity and its associated chronic illnesses but is difficult to maintain for a long time. Intermittent fasting is an alternative and easily applicable dietary intervention for caloric restriction. Moreover, intermittent fasting has beneficial effects equivalent to those of caloric restriction in terms of body weight control, improvements in glucose homeostasis and lipid profiles, and anti-inflammatory effects. In this review, the beneficial effects of intermittent fasting are discussed.

• BMB Reports
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• v.53 no.4
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• pp.181-190
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• 2020

Protein phosphatase 4 (PP4), one of serine/threonine phosphatases, is involved in many critical cellular pathways, including DNA damage response (DNA repair, cell cycle regulation, and apoptosis), tumorigenesis, cell migration, immune response, stem cell development, glucose metabolism, and diabetes. PP4 has been steadily studied over the past decade about wide spectrum of physiological activities in cells. Given the many vital functions in cells, PP4 has great potential to develop into the finding of key working mechanisms and effective treatments for related diseases such as cancer and diabetes. In this review, we provide an overview of the cellular and molecular mechanisms by which PP4 impacts and also discuss the functional significance of it in cell health.

• YAKHAK HOEJI
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• v.56 no.6
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• pp.364-365
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• 2012

Liver is the major organ to regulate the systemic glucose homeostasis and insulin resistance. Excess energy intake leads to triglyceride accumulation in adipose tissue first and subsequent accumulation in liver, resulting in obesity and type 2 diabetes. The representative pathological animal model for obesity associated insulin resistance is a high fat diet (HFD) fed mice model. Given the essential role of liver fat accumulation in developing systemic insulin resistance in obesity, I measured the liver triglyceride contents in HFD fed mice as a function of time. As such, in this report, I show the cause and effect relationship with regard to time during a HFD feeding between a variety of factors that are related to systemic insulin resistance including glucose intolerance, plasma insulin level and inflammatory gene expression in liver and adipose tissue.