• Journal of Society of Preventive Korean Medicine
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• v.22 no.2
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• pp.77-107
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• 2018

Objectives : In present study, therefore, possible beneficial pharmacological activities of standard potato protein extracts (SPE) were observed on the mild diabetic obese mice. Methods : After end of 12 weeks of continuous oral administrations of three different dosages of SPE 400, 200 and 100 mg/kg, or metformin 250 mg/kg, analyzed the hepatoprotective, hypolipidemic, hypoglycemic, nephroprotective and anti-obesity effects, separately. In addition, liver antioxidant defense systems were additionally measured with lipid metabolism-related genes expressions and hepatic glucose-regulating enzyme activities for action mechanism. Results : All of diabetes and related complications including obesity were significantly inhibited by treatment of SPE 400, 200 and 100 mg/kg, dose-dependently, and they also dramatically normalized the hepatic lipid peroxidation and depletion of liver endogenous antioxidant defense system, the changes of the hepatic glucose-regulating enzyme activities, also changes of the lipid metabolism-related genes expressions including hepatic $AMPK{\alpha}1$ and $AMPK{\alpha}2$ mRNA expressions, dose-dependently. Especially, SPE 200 mg/kg constantly showed favorable inhibitory activities against type II diabetes and related complications as comparable to those of metformin 250 mg/kg in HFD mice, respectively. Conclusions : The present work demonstrated that SPE 400, 200 and 100 mg/kg showed favorable anti-diabetic and related complications including obesity refinement activities in HFD mice, through AMPK upregulation mediated hepatic glucose enzyme activity and lipid metabolism-related genes expression, antioxidant defense system and pancreatic lipid digestion enzyme modulatory activities.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.335-350
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• 2014

Compared to the large numbers of studies on the diabetes, hyperlipidemia and cancer therpeutic effects of ginseng, the anti-obese effect and mechanisms of ginsengs have not been studied as much. To determine the effects of ginseng on obesity, 14 keywords (ginseng, ginsenoside, obesity, weight, fat, diet, overeat, appetite, lipid, 3T3-L1, adipocyte, food intake, adipogenesis and lipolysis) were combined in searching a database. Fifty-six articles published from 1983 to 2012 as well as 656 patents registered until Aug $17^{th}$, 2012, were screened for anti-obese effects of ginseng. In the classification of experimental methods, 16 papers on 3T3-L1 cells, 38 papers on animals and three papers on human were reviewed. In terms of obese mechanisms of action, the most commonly used biomarkers were in order of lipid profiles > weight change > blood glucose > adipocytokine. Most ginseng studies on obesity focused on AMPK, $PPAR{\gamma}$, GLUT-4, PI3K and SREBP-1. Korean white ginseng extracts and Re repressed the lipogenesis genes such as PPARc2, SREBP-1c, LPL, FAS and DGAT1. However, ginseng or ginsenosides, PD (Rb1) and PT (Re), showed different or contradictory results. Water and ethanol extraction of ginseng showed contradictory effects on the secretion of inflammatory cytokines, wheras IL-6 was repressed by ethanol extracts and TNF-${\alpha}$ repressed by Re in vitro. Based on the literature, further studies on anti-obese mechanisms of ginseng, such as the inflammation-related obesity or cross signals between the adipocytes and the environments, are needed, instead of more studies on its hypolipidemic and hypoglycemic effects.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.2
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• pp.95-111
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• 2022

Chronic obstructive pulmonary disease (COPD) is an important healthcare problem worldwide. Often, glucocorticoid (GC) resistance develops during COPD treatment. As a classic hypoglycemic drug, metformin (MET) can be used as a treatment strategy for COPD due to its anti-inflammatory and antioxidant effects, but its specific mechanism of action is not known. We aimed to clarify the role of MET on COPD and cigarette smoke extract (CSE)-induced GC resistance. Through establishment of a COPD model in rats, we found that MET could improve lung function, reduce pathological injury, as well as reduce the level of inflammation and oxidative stress in COPD, and upregulate expression of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), multidrug resistance protein 1 (MRP1), and histone deacetylase 2 (HDAC2). By establishing a model of GC resistance in human bronchial epithelial cells stimulated by CSE, we found that MET reduced secretion of interleukin-8, and could upregulate expression of Nrf2, HO-1, MRP1, and HDAC2. MET could also increase the inhibition of MRP1 efflux by MK571 significantly, and increase expression of HDAC2 mRNA and protein. In conclusion, MET may upregulate MRP1 expression by activating the Nrf2/HO-1 signaling pathway, and then regulate expression of HDAC2 protein to reduce GC resistance.

• Journal of Pharmaceutical Investigation
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• v.40 no.3
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• pp.175-180
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• 2010

Albumin-modification has been viewed as one of the most effective ways of extending the short in vivo lifetimes of peptide drugs by delaying glomerular filtration. In this study, we describe a new type 2 anti-diabetic exendin-4 (Ex4) peptide derivative with significant binding ability to human serum albumin (HSA). This exendin-4 derivative consists of a 4-branched polyethylene glycol $(PEG)_{5k}$ (Mw: 20 kDa) modified with three stearylamines ($C_{18}-NH_2$) and one exendin-4 on its branches. PEG and stearylamine were selected to provide functionality to increase molecular size and bind to albumin, respectively. This derivative ($3C_{18}-4PEG_{5k}$-Ex4) was shown to have larger molecular size (Ca. 152 kDa) than actual (25.0 kDa) when subjected to size-exclusion chromatography, and the fluorescein-tagged $3C_{18}-4PEG_{5k}$-Ex4 displayed significant binding to the HSA-immobilized Sepharose CL-4B resin using confocal laser scanning microscopy. Furthermore, $3C_{18}-4PEG_{5k}$-Ex4 was found to have acceptable anti-hyperglycemic efficacy via three consecutive oral glucose tolerance testings (OGTT) in fasted type 2 diabetic db/db mice. The $HD_{total}$ value ($57.6{\pm}12.3%$) of $3C_{18}-4PEG_{5k}$-Ex4 at a 50 nmol/kg dose was 2-fold greater than that ($31.0{\pm}8.7%$) of native exendin-4 in non-fasted db/db mice. Especially, the blood glucose levels in the mice group treated with $3C_{18}-4PEG_{5k}$-Ex4 did not rebound to ~150 mg/dL until 24 h after the injection, which obviously shows the extended hypoglycemia. We believe that this derivative has great pharmaceutical potential as a novel long-acting type 2 anti-diabetic injection treatment.

• The Korean Journal of Pharmacology
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• v.24 no.1
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• pp.125-134
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• 1988

A single i.v. dose of streptozotocin (65 mg/kg) given to rats has produced a marked hyper-glycemia (>500 mg serum glucose/dl). Since the Atractylodis Rhizoma is known to have hypo-glycemic action, the water extracts of Atractylodis Rhizoma (ARWE) was given to the streptozotocin-induced (SZ) hyperglycemic rats. To determine whether ARWE has the anti-hyperglycemic effects, two different daily doses of ARWE (i.e.0.2 g/kg and 2.0 g/kg) were given orally to the SZ rats for up to 8 days. Thereupon, serum levels of glucose, insulin, amylase and cholesterol were determined on days 1, 3 and 8, following the initial and repeated daily administrations of ARWE. On day 8, glycogen content and glucose-6-phosphatase activity in the liver were assayed. Results showed that ARWE decreased the serum glucose levels, which had been markedly elevated by the SZ pre-treatment. In support of this, the serum insulin level, which had been quickly lowered by the SZ pre-treatment $(20{\mu}U/ml)$, was quickly elevated in the ARWE dose dependent manner that, at 2.0 g/kg ARWE, the serum insulin level was increased $(20{\mu}U/ml)$ above the normal level $(42{\mu}U/ml)$. Also, the serum amylase level, which was steadily decreasing after the SZ pre-treatment, was restored to the normal level folowing 8 day of ARWE (2.0 g/kg) treatment. Hepatic glycogen content and glucose-6-phosphatase activity, which decreased and increased, respectively in the 52 treatment group, were restored toward the normal level in SZ plus ARWE group.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.153-160
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• 2016

The objective was to investigate the hypoglycemic action of catalpol in spontaneous diabetes db/db mice. 40 db/db mice were randomly divided into five groups: model control gourp; db/db plus catalpol 40, 80, 120 mg/kg body wt. groups and db/db plus metformin 250 mg/kg group. Age-matched db/m mice were selected as normal control group. The mice were administered with corresponding drugs or solvent by gavage for 4 weeks. The oral glucose tolerance test was carried out at the end of $3^{rd}$ week. After 4 weeks of treatment, the concentrations of fasting blood glucose (FBG), glycated serum protein (GSP), insulin (INS), triglyceride (TG), total cholesterol (TC) and adiponection (APN) in serum were detected. The protein expressions of phosphorylation-$AMPK{\alpha}$1/2 in liver, phosphorylation-$AMPK{\alpha}$1/2 and glucose transporter-4 (GLUT-4) in skeletal muscle and adipose tissues were detected by western blot. Real time RT-PCR was used to detect the mRNA expressions of acetyl-CoA carboxylase (ACC) and Hydroxymethyl glutaric acid acyl CoA reductase (HMGCR) in liver. Our results showed that catalpol could significantly improve the insulin resistance, decrease the serum concentrations of INS, GSP, TG, and TC. The concentrations of APN in serum, the protein expression of phosphorylation-$AMPK{\alpha}$1/2 in liver, phosphorylation-$AMPK{\alpha}$1/2 and GLUT-4 in peripheral tissue were increased. Catalpol could also down regulate the mRNA expressions of ACC and HMGCR in liver. In conclusion, catalpol ameliorates diabetes in db/db mice. It has benefit effects against lipid/glucose metabolism disorder and insulin resistance. The mechanism may be related to up-regulating the expression of phosphorylation-$AMPK{\alpha}$1/2.

• Proceedings of the Ginseng society Conference
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• 2007.12a
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• pp.57-58
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• 2007

Purpose: Ginseng is a well-known medical plant used in traditional Oriental medicine. Korean red ginseng (KRG) has been known to have potent biological activities such as radical scavenging, vasodilating, anti-tumor and anti-diabetic activities. However, the mechanism of the beneficial effects of KRG on diabetes is yet to be elucidated. The present study was designed to investigate the anti-diabetic effect and mechanism of KRG extract in C57BL/KsJ db/db mice. Methods: The db/db mice were randomly divided into six groups: diabetic control group (DC), red ginseng extract low dose group (RGL, 100 mg/kg), red ginseng extract high dose group (RGH, 200 mg/kg), metformin group (MET, 300 mg/kg), glipizide group (GPZ, 15 mg/kg) and pioglitazone group (PIO, 30 mg/kg), and treated with drugs once per day for 10 weeks. During the experiment, body weight and blood glucose levels were measured once every week. At the end of treatment, we measured Hemoglobin A1c (HbA1c), blood glucose, insulin, triglyceride (TG), adiponectin, leptin, non-esterified fatty acid (NEFA). Morphological analyses of liver, pancreas and white adipose tissue were done by histological observation through hematoxylin-eosin staining. Pancreatic islet insulin and glucagon levels were detected by double-immunofluorescence staining. To elucidate an action of mechanism of KRG, DNA microarray analyses were performed, and western blot and RT-PCR were conducted for validation. Results: Compared to the DC group mice, body weight gain of PIO treated group mice showed 15.2% increase, but the other group mice did not showed significant differences. Compared to the DC group, fasting blood glucose levels were decreased by 19.8% in RGL, 18.3% in RGH, 67.7% in MET, 52.3% in GPZ, 56.9% in PIO-treated group. With decreased plasma glucose levels, the insulin resistance index of the RGL-treated group was reduced by 27.7% compared to the DC group. Insulin resistance values for positive drugs were all markedly decreased by 80.8%, 41.1% and 68.9%, compared to that of DC group. HbA1c levels in RGL, RGH, MET, GPZ and PIO-treated groups were also decreased by 11.0%, 6.4%, 18.9%, 16.1% and 27.9% compared to that of DC group, and these figure revealed a similar trend shown in plasma glucose levels. Plasma TG and NEFA levels were decreased by 18.8% and 16.8%, respectively, and plasma adiponectin and leptin levels were increased by 20.6% and 12.1%, respectively, in the RGL-treated group compared to those in DC group. Histological analysis of the liver of mice treated with KRG revealed a significantly decreased number of lipid droplets compared to the DC group. The control mice exhibited definitive loss and degeneration of islet, whereas mice treated with KRG preserved islet architecture. Compared to the DC group mice, KRG resulted in significant reduction of adipocytes. From the pancreatic islet double-immunofluorescence staining, we observed KRG has increased insulin production, but decreased glucagon production. KRG treatment resulted in stimulation of AMP-activated protein kinase (AMPK) phosphorylation in the db/db mice liver. To elucidate mechanism of action of KRG extract, microarray analysis was conducted in the liver tissue of mice treated with KRG extract, and results suggest that red ginseng affects on hepatic expression of genes responsible for glycolysis, gluconeogenesis and fatty acid oxidation. In summary, multiple administration of KRG showed the hypoglycemic activity and improved glucose tolerance. In addition, KRG increased glucose utilization and improved insulin sensitivity through inhibition of lipogenesis and activation of fatty acid $\beta$-oxidation in the liver tissue. In view of our present data, we may suggest that KRG could provide a solid basis for the development of new anti-diabetic drug.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.321-327
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• 2006

This study was performed to investigate the hypoglycemic effect of pine needle extract oil against type 2 diabetes. Six-week-old male C57BL/Ks(db/db) mice were divided into four groups : negative control, pine needle extract oil low dose, high dose and positive control groups, which fed daily for 6 weeks with corn oil, pine needle extract oil 112.5 mg/kg, 450 mg/kg or metformin (150 mg/kg ), respectively. The oral administration of the pine needle extract oil resulted in the significant and dose-dependent decreases of blood glucose levels in comparison with corn oil treatment. The levels of HbAlc showed a tendency of the decrease by the high dose treatment of the pine needle extract oil and were positively correlated with blood glucose levels (r=0.5046, p=0.0023) . However, the levels of serum insulin and C-peptide were not affected by pine needle extract oil or metformin treatments. The levels of serum leptin, which is related with the insulin sensitivity, showed a tendency of the increases by pine needle extract oil treatment and were negatively correlated to blood glucose levels (r=-0.4754, p=0.0052). In conclusion, these results suggest that the pine needle extract oil have a potential for the oral anti-hyperglycemic agent and the mode of action may be related with the improvement of the insulin sensitivity through blood leptin.