• The Korea Journal of Herbology
• /
• v.31 no.1
• /
• pp.1-5
• /
• 2016

Objectives : The purpose of this study was to investigate inhibitory effects of steamed Polygonatum odoratum extract (POE) on insulin resistance in rat skeletal muscle cells, L6 cells.Methods : Polygonatum odoratum (P. odoratum) extract was extracted with ethyl acetate. Activity of α-glucosidase in POE was measured for blood glucose regulation. MTT assay was examined for cell toxicity. Western blot analysis for measurement of adiponectine, peroxisome proliferator-activated receptorγ (PPARγ), insulin receptor substrate (IRS), glucose transporter 4 (Glut-4) and phosphorylation of serine/threonine-specific protein kinase (Akt) expressions were performed. Akt signaling pathway were analyzed with LY294002, which is a specific PI3K/Akt inhibitor.Results : The results revealed that POE inhibited α-glucosidase activity. Treatment of POE in L6 cells inhibited the differentiation of L6 cells compared to those of vehicl control. Additionally, protein expressions of adiponectine, PPARγ, IRS and Glut-4 were significantly regulated compared to those of vehicle control (p < 0.05), respectively. Futhermore, phosphorylation of Akt was increased in L6 cells treated with POE compared to that of vehicle control (p < 0.05). pAkt expression was significantly accentuated with Akt inhibitor (LY294002).Conclusions : These results suggest that POE may have potential as a natural agent for prevention/improvement of diabetes, especially, regulation of blood glucose. Therefore, further additional study should be conducted to elucidate in depth the pharmaceutical efficacy of these.

• Food Science and Biotechnology
• /
• v.16 no.2
• /
• pp.212-217
• /
• 2007

Fucoidan (fucan sulfate) is a fucose-containing sulfated polysaccharide from brown algae such as Fucus vesiculosus, Ecklonia kurome, and Cladosiphon okamuranus. The aim of this study was to investigate the effect of fucoidan on the expression of diabetes-related genes in mouse cell line 3T3-L1. 3T3-L1 adipocytes were cultured for 48 hr with or without fucoidan (10, 100, and 500 ppm) on a 60 mm dish. Reverse transcription polymerase chain reaction (RT-PCR) was used for measurement of peroxisome proliferators activated receptor ${\gamma}\;(PPAR{\gamma})$, CCAAT/enhancer binding protein ${\alpha}\;(C/EBP{\gamma})$, and glucose transporter 4 (GLUT4) RT-PCR analysis revealed that expression level of GLUT4, $PPAR{\gamma}$, and $C/EBP{\alpha}$ mRNAs increased with fucoidan treatment from 10 to 500 ppm in a dose-dependent manner. Fucoidan appears to enhance insulin sensitivity by increasing the expression level of diabetes-related genes in 3T3-L1 adipocytes. Therefore, fucoidan is potentially useful as a natural therapeutic material for hyperglycemia in type II diabetes patients.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.6
• /
• pp.1225-1238
• /
• 2015

In this research, we fit various survival models and conduct tests and estimation for the hazard change-point with the rectal cancer data. By the log-rank tests, at significance level ${\alpha}=0.10$, survival functions are significantly different according to the uniporter of glucose (GLUT1), clinical stage (cstage) and pathologic stage (ypstage). From the Cox proportional hazard model, the most significant covariates are GLUT1 and ypstage. Assuming that the rectal cancer data follows the exponential distribution, we estimate one hazard change-point using Matthews and Farewell (1982), Henderson (1990) and Loader (1991) methods.

• Journal of Acupuncture Research
• /
• v.22 no.3
• /
• pp.77-92
• /
• 2005

Objective : The aim of the study was to investigate the effect of Acanthopanax senticocus(AS) herbal acupuncture on the metabolic syndrome in high-fat diet fed mice. Methods : ICR mice were fed with high-fat diet to induce the metabolic syndrome. During the inducement of the metabolic syndrome, the groups were treated with AS herbal acupuncture with different concentrations(125mg/kg, 250mg/kg and 500mg/kg) to the point of Sinsu(BL23) everyday for 5 weeks. Thereafter, body weight, feed efficiency ratio, blood pressure, blood glucose, insulin level, insulin resistance, oral glucose tolerance test(OGTT), lipid profile(TG, TC, HDL-C, LDL-C, NEFA), mass of liver, histology of white adipose tissue(WAT) and brown adipose tissue(BAT), and expression of GLUT-4 and UCP-1 mRNA were measured. Results : The risk factors of metabolic syndrome such as obesity, non-insulin dependent diabetes mellitus(NIDDM), insulin resistance, hypertension, dyslipidemia were aggravated by high-fat diet for 5-weeks. AS herbal acupuncture inhibited the development of weight gain, hyperglycemia, hyperinsulinemia, insulin resistance, hypertension, dylipidemia and expression of GLUT-4 in WAT and UCP-1 mRNA in BAT, and also improved oral glucose intolerance and distribution of adipose tissue.

• Food Science and Preservation
• /
• v.22 no.6
• /
• pp.893-900
• /
• 2015

In this study, we evaluated the antidiabetic effect of a submerged culture of Ceriporia lacerata mycelium (CL01) on hematological indices, as well as protein and mRNA expression of the insulin-signaling pathway, in db/db mice. After CL01 was administrated for 4 weeks, blood glucose levels decreased consistently, and plasma insulin and c-peptide levels each decreased by roughly 55.8%, 40% of those in the negative control (p<0.05). With regard to HOMA-IR, an insulin resistance index, insulin resistance of the CL01-fed group improved over that of the negative control group by about 62% (p<0.05). In addition, we demonstrated that the protein expression levels of pIR, pAkt, pAMPK, and GLUT4 and the mRNA expression levels of Akt2, IRS1, and GLUT4 in the muscle cells of db/db mice increased in the CL01-fed group compared to the corresponding levels in the control group. These results demonstrate that CL01 affects glucose metabolism, upregulates protein and gene expression in the insulin-signaling pathway, and decreases blood glucose levels effectively by improving insulin sensitivity. More than 90% of those who suffer from type 2 diabetes are more likely to suffer from hyperinsulinemia, hypertension, obesity, and other comorbidities because of insulin resistance. Therefore, it is possible that CL01 intake could be used as a fundamental treatment for type 2 diabetes by lowering insulin resistance, and these results may prove be useful as basic evidence for further research into the mechanisms of a cure for type 2 diabetes.

• Journal of Applied Biological Chemistry
• /
• v.62 no.4
• /
• pp.417-424
• /
• 2019

The aim of this study is to investigate the effect of Lespedeza maximowiczii var. tricolor Nakai (LMTN) on glucose metabolism. LMTN extract significantly enhanced the glucose uptake and lipid accumulation in 3T3-L1 adipocytes compared with control. Also, LMTN extract in 3T3-L1 adipocytes significantly increased the protein expression of peroxisome proliferator-activated receptor (PPAR)γ, insulin receptor substrate-1, and glucose transporter (GLUT)4. The regulatory effect on glucose uptake or insulin signal transduction of LMTM extract was lower than troglitazone or pinitol such as the positive control, but increased PPARγ activation. Additionally, LMTM extract has an insulin-mimetic effect. In db/db mice, LMTN extract (250 mg/kg BW) significantly reduced water and food intake, blood glucose, and level of plasma triglyceride and total cholesterol. Furthermore, the expression of PPARã and GLUT4 mRNA in adipose or muscle tissue effectively was increased by oral treatment of LMTN extract. Thus, our results suggest that LMTN extract improves the glucose metabolism through PPARγ and insulin-mimetic effect in 3T3-L1 adipocytes and db/db mice.

• Journal of Applied Biological Chemistry
• /
• v.64 no.1
• /
• pp.89-96
• /
• 2021

The aim of this study is to examine the effect of Caulerpa okamurae ethanol extract (COE) on glucose metabolism and insulin sensitivity as one of the drug targets for treatment of type2 diabetes. COE significantly inhibited protein tyrosine phosphatase (PTP1B) and dipeptidyl peptidase-IV (DPP-IV) enzyme activities in vitro assay. Also, COE significantly enhanced the glucose uptake and the expression of insulin receptor substrate-1 (IRS-1) and glucose transporter4 (GLUT4) proteins in 3T3-L1 adipocytes or zebrafish larvae compared with control. In dexamethasone-induced resistance model of L6 myotubes, the protein expression of insulin signaling and glucose uptake was effectively increased by the treatment of COE. In contrast, the elevated phosphorylation of IRS-1 Ser307 was normally suppressed by treatment of COE. However, COE had no effect on insulin secretion in pancreatic beta cells. Thus, our results suggest that COE improves the glucose metabolism and insulin sensitivity through the regulation of insulin signaling and GLUT4 protein in insulin's target cells and zebrafish larvae.

• Korean Journal of Food Science and Technology
• /
• v.52 no.2
• /
• pp.191-199
• /
• 2020

The purpose of this study was to isolate novel lactic acid bacteria to ferment mulberry leaf extract (MLE) and to investigate its anti-diabetic effect. Lactobacillus plantarum SG-053 isolated from gatkimchi was selected to ferment MLE because it exhibited high α-glucosidase inhibitory activity (96.8%) and enhanced the content of 1-deoxynojirimycin (DNJ), an anti-diabetic substance, in fermented MLE up-to 2.2 times. MLE fermented with L. plantarum SG-053 (FMLE) showed growth promoting activity against L6 myotubes and increased the gene expressions of IRS-1, PI3K p85α, and GLUT-4 up-to 1.4, 2.2, and 1.4 times, respectively, and 2-deoxyglucose uptake up-to 40.7%. In rat skeletal muscle tissue, the expressions of PI3K p85α and GLUT-4 increased by 6.4 and 2.1 times, respectively. These results suggest that L. plantarum SG-053 could enhance the DNJ content of MLE by fermentation and that FMLE is effective in ameliorating insulin resistance via activation of the insulin signaling pathway.

• Biomolecules & Therapeutics
• /
• v.31 no.6
• /
• pp.619-628
• /
• 2023

In the modern era, chronic kidney failure due to diabetes has spread across the globe. Prunetin (PRU), a component of herbal medicines, has a broad variety of pharmacological activities; these may help to slow the onset of diabetic kidney disease. The anti-nephropathic effects of PRU have not yet been reported. The present study explored the potential nephroprotective actions of PRU in diabetic rats. For 28 days, nephropathic rats were given oral doses of PRU (20, 40, and 80 mg/kg). Body weight, blood urea, creatinine, total protein, lipid profile, liver marker enzymes, carbohydrate metabolic enzymes, C-reactive protein, antioxidants, lipid peroxidative indicators, and the expression of insulin receptor substrate 1 (IRS-1) and glucose transporter 2 (GLUT-2) mRNA genes were all examined. Histological examinations of the kidneys, liver, and pancreas were also performed. The oral treatment of PRU drastically lowered the blood glucose, HbA1c, blood urea, creatinine, serum glutamic-oxaloacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, lipid profile, and hexokinase. Meanwhile, the levels of fructose 1,6-bisphosphatase, glucose-6-phosphatase, and phosphoenol pyruvate carboxykinase were all elevated, but glucose-6-phosphate dehydrogenase dropped significantly. Inflammatory marker antioxidants and lipid peroxidative markers were also less persistent due to this administration. PRU upregulated the IRS-1 and GLUT-2 gene expression in the nephropathic group. The possible renoprotective properties of PRU were validated by histopathology of the liver, kidney, and pancreatic tissues. It is therefore proposed that PRU (80 mg/kg) has considerable renoprotective benefits in diabetic nephropathy in rats.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.7
• /
• pp.963-971
• /
• 2014

This study investigated the effects of exercise intensity on PGC-$1{\alpha}$, PPAR-${\gamma}$, and insulin resistance in skeletal muscle of high fat diet-fed Sprague-Dawley rats. Forty rats were randomly divided into five groups: sedentary control group (SED), high fat diet group (HF), high fat diet+low-intensity exercise group (HFLE, 22 m/min, 60 min, 6 days/week), high fat diet+moderate-intensity exercise group (HFME, 26 m/min, 51 min), and high fat diet+high-intensity exercise group (HFHE, 30 m/min, 46 min). After 4 weeks of high fat diet and endurance exercise training, the lipid profiles, insulin, and glucose concentrations were determined in plasma. PGC-$1{\alpha}$, PPAR-${\gamma}$, and GLUT-4 contents were measured in plantaris muscle. The rate of glucose transport in soleus muscle was determined under submaximal insulin concentration ($1,000{\mu}IU/mL$ insulin, 20 min) during muscle incubation. Plasma glucose during oral glucose tolerance test in HF was significantly greater than that in SED, and plasma glucose levels in the three exercise (EX) groups were significantly lower that those in SED and HF at 30 and 60 min, respectively (P<0.05). Plasma insulin levels in the EX groups were significantly reduced by 60 min compared to that in HF (P<0.05). The protein expression level of PGC-$1{\alpha}$ as well as muscle glucose uptake were significantly higher in SED and HF than those in the three EX groups (P<0.05), and HFHE showed significantly higher levels than HFLE and HFME. Expression levels of GLUT-4 and PPAR-${\gamma}$ were significantly higher in the HFLE, HFME, and HFHE groups compared to the SED and HF (P<0.05). Therefore, the results of this study indicate that 4 weeks of high fat diet significantly developed whole body insulin resistance but did not affect PGC-$1{\alpha}$, PPAR-${\gamma}$, or the glucose transport rate in skeletal muscle, and exercise training was able to attenuate deteriorated whole body insulin resistance due to high fat diet. In addition, high intensity training significantly affected PGC-$1{\alpha}$ expression and the glucose transport rate of skeletal muscle in comparison with low and middle training intensities.