• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.302-307
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• 2009

The present study was designed to clarify the antidiabetic activity and mechanism of Dioscorea rhizome in diabetic db/db mice. Mice were administered Dioscorea rhizome and rosiglitazone orally for 7 weeks and the effects of these compounds on fasting blood glucose, glucose tolerance and intestinal disaccharidase activity in db/db mice were evaluated. The fasting serum glucose of the D. rhizome treated group was reduced when compared with that of the db/db control group. In addition, the disaccharidase activities in homogenates of the proximal, middle and distal segment of the small intestine were significantly decreased response to D. rhizome treatment, especially in the middle segment. These results suggest that D. rhizome decreases blood glucose via a decrease in the activity of disaccharidase in the mucosa of the middle region of the small intestine in db/db mice.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.4
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• pp.281-296
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• 2021

The beneficial effects of hypoxic preconditioning are abolished in the diabetes. The present study was designed to investigate the protective effects and mechanisms of repeated episodes of whole body hypoxic preconditioning (WBHP) in db/db mice. The protective effects of preconditioning were explored on diabetes-induced vascular dysfunction, cognitive impairment and ischemia-reperfusion (IR)-induced increase in myocardial injury. Sixteen-week old db/db (diabetic) and C57BL/6 (non-diabetic) mice were employed. There was a significant impairment in cognitive function (Morris Water Maze test), endothelial function (acetylcholine-induced relaxation in aortic rings) and a significant increase in IR-induced heart injury (Langendorff apparatus) in db/db mice. WBHP stimulus was given by exposing mice to four alternate cycles of low (8%) and normal air O₂ for 10 min each. A single episode of WBHP failed to produce protection; however, two and three episodes of WBHP significantly produced beneficial effects on the heart, brain and blood vessels. There was a significant increase in the levels of brain-derived neurotrophic factor (BDNF) and nitric oxide (NO) in response to 3 episodes of WBHP. Moreover, pretreatment with the BDNF receptor, TrkB antagonist (ANA-12) and NO synthase inhibitor (L-NAME) attenuated the protective effects imparted by three episodes of WBHP. These pharmacological agents abolished WBHP-induced restoration of p-GSK-3β/GSK-3β ratio and Nrf2 levels in IR-subjected hearts. It is concluded that repeated episodes of WHBP attenuate cognitive impairment, vascular dysfunction and enhancement in IR-induced myocardial injury in diabetic mice be due to increase in NO and BDNF levels that may eventually activate GSK-3β and Nrf2 signaling pathway to confer protection.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.151-156
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• 2003

This study was carried out to investigate the optimal mixed extract with Bambusae Caulis in Liquamen in order to strengthen anti-diabetic effects on the hyperglycemia induced by streptozotocin in mice. The original Bambusae Caulis in Liquamen filtered and refined. The effects of Bambusae Caulis in Liquamen and Mixed extracts(Bamboo Juice) with Bambusae Caulis in Liquamen were administered to mice for 4weeks and its anti-diabetic effect examined. Mice used in this experiment were divided into three groups and saline(control), Bamboo Juice mixed with refined Bambusae Caulis in Liquamen(BJ＋BCL.D) and distrilled water mixed with refined Bambusae Caulis in Liquamen(DW＋BCL.D) were given orally for 28days respectively. And then, experemental groups were observed in terms of blood sugar, creatinine, BUN and GPT. The amount of glucose was significantly decreased in the Bambusae Caulis in Liquamen and Mixed extracts(Bamboo Juice) with Bambusae Caulis in Liquamen-treated groups compared with the control group(P<0.01). The amount of creatinine, BUN and GPT did not show any differences among Control, BJ＋BCL.D and DW＋BCL.D groups. In conclusion. it was found that Bambusae Caulis in Liquamen and Mixed extracts(Bamboo Juice) with Bambusae Caulis in Liquamen were nontoxic to kidney and liver and also effective on murine hyperglycemia induced with STZ. Mixed extracts(Bamboo Juice) were more effective for decreasing blood glucose than Bambusae Caulis in Liquamen D. BJ＋BCL.D can be used as optimal mix material with Bambusae Caulis in Liquamen D for control Diabetes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.5
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• pp.707-713
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• 2012

Taraxacum coreanum Nakai (TM) has been investigated for its antidiabetic activity in streptozotocin induced diabetic animals, but few studies have been conducted to evaluate its efficacy for treatment of type II diabetic mice. This study was designed to evaluate the efficacy of the water extracts of TM for the treatment of type II diabetes. Twenty four mice(C57BLKS/J Iar $-+Lepr^{db}/+Lepr^{db}$) with type II diabetes were randomly assigned either to a experimental group A (leaves extraction of TM), experimental group B(roots extraction of TM), experimental group C(leaves, roots and flowers extraction of TM) or control group. Water extracts of TM were ingested for 10 weeks. The changes of body weight, level of blood glucose, numerical change of insulin-immunoreactive cells and level of blood insulin were measured after treatment of water extracts of TM. A reduction of the blood glucose level after treatment of TM was observed in all the experimental groups. Especially, experimental C group showed significant reduction of blood glucose level compared with control group. Experimental C group induced an increase the level of blood insulin and density of insulin immunoreactive cells after treatment of TM. These results show that water extracts of TM can improve the severity in type II diabetic mice.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.163-168
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• 2013

In this study, we investigated the inhibitory effects of Baechu kimchi added Ecklonia cava on the activities of ${\alpha}$-glucosidase and ${\alpha}$-amylase and its alleviating effect on the postprandial hyperglycemia in STZ-induced diabetic mice. Baechu kimchi added Ecklonia cava (BKE, 15%) was fermented at $5^{\circ}C$ for 28 days. Optimum ripened BKE was used in this study as it showedthe strongest inhibitory activities on ${\alpha}$-glucosidase and ${\alpha}$-amylaseby fermentation time among the BKEs in our previous study. The BKE was extracted with 80% methanol and the extract solution was concentrated, and then used in this study. The BKE extract showed higher inhibitory activities than Baechu kimchi extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of the BKE extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.58 and 0.35 mg/mL, respectively; BKE exhibited a lower ${\alpha}$-glucosidase inhibitory activity but a higher ${\alpha}$-amylase inhibitory activity than those of acarbose. The BKE extract alleviated postprandial hyperglycemia caused by starch loading in normal and streptozotocin- induced diabetic mice. Furthermore, the BKE extract significantly lowered the incremental area under the curve in both normal and diabetic mice (P<0.05). These results indicated that the BKE extract may delay carbohydrate digestion and thus glucose absorption.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.345-350
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• 2006

The pharmacological properties of ginseng are mainly attributed to ginsenosides, the active constituents that are found in the extracts of different species of ginseng. Lately; the studies on ginsenosides are mainly focused on IH-901, a major intestinal bacterial metabolite of ginsenosides. In this study; we examined the anti-diabetic activity of IH-901 in C57BU61 db/db mice model. IH-901 was administrated orally at a dose of 20 mg/kg for 5 weeks. During the experimental period, body weight and blood glucose levels were measured every week. After 5 weeks, db/db mice were sacrificed and diabetic parameters were analyzed. IH-901 treated group showed a significant decrease in fasting blood glucose levels (from 10.5 mM to 9.4 mM), insulin resistance index (from 163.6 to 100.2) and triglyceride levels (from 115.3 to 70.1) compared to the diabetic control. In Pancreatic islets morphology; IH-901 treated group revealed much less infltrated mononuclear cells, indicating that IH-901 recovered ${\beta}$-cell damage due to hyperglycemia. In addition, IH-901 upregulated expressions of glucose transporter 4 (GLUT4) and PPAR-${\gamma}$ in skeletal muscle and adipose tissue, respectively. Taken together IH-901might be a potential anti-hyperglycemic agent with insulin sensitizing effect.

• The Korea Journal of Herbology
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• v.30 no.2
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• pp.1-9
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• 2015

Objectives : The present study was conducted to examine whether Toosendan Fructus has an ameliorative effect on diabetes-induced alterations such as oxidative stress and inflammation in the pancreas of non-obese diabetic (NOD) mice, a model of human type I diabetes. Methods : Extracts of Toosendan Fructus (ETF) were administered to NOD mice at three doses (50 mg/kg, 100 mg/kg and 200 mg/kg). Mice at 18 weeks of age were measured glucose tolerance using intraperitoneal glucose tolerance test. After 28 weeks of ETF treatment, glucose, total cholesterol (TC), triglyceride (TG), and proinflammatory cytokines in serum, western blot analyses and a histopathological examination in pancreas tissue, and on the onset of diabetes were investigated. Results : The results showed that levels of glucose, glucose tolerance, TC, TG, interferon-${\gamma}$, interleukin (IL)-1 ${\beta}$, IL-6, and IL-12 in serum were down-regulated, while IL-4, IL-10, SOD, and catalase significantly increased. In addition, ETF improved protein expression of proinflammatory mediaters (such as cyclooxygenase-2, and inducible nitric oxide synthase) and a proapoptotic protein (caspase-3) in the pancreatic tissue. Also, in the groups treated with ETF (100 mg/kg or 200 mg/kg), insulitis and infiltration of granulocytes were alleviated. Conclusions : Based on these results, the anti-diabetic effect of ETF may be due to its anti-inflammatory and antioxidant effect. Our findings support the therapeutic evidence for Toosendan Fructus ameliorating the development of diabetic pancreatic damage via regulating inflammation and apoptosis. Our future studies will be focused on the search for active compounds in these extracts.

• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.337-342
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• 2002

The effect of water extract composed of panax ginseng radix rubra, acanthopanacis cortex, and cordyceps (PAC) on diabetic animal models were investigated in two different diabetic animal models. FAC water extract significantly reduced the plasma glucose levels on day 30 as compared with the diabetic control group in $KKA^Y$ obese, hyperglycemic and hyperglycemic and hyperinsulinemic mice, and also reduced the plasma glucose levels as well as total cholesterol in multiple low dose (MLD) strep tozotocin-induced diabetic SD rats. PAC water extract also showed an inhibitory effect on reduction of body weight and on development of MLD STZ-induced diabetic state. Elevated kidney hypertrophy, which is a characteristic feature shown in early stage of diabetic nephropathy and calculated as the ratio of kidney mass (g) relative to the body weight (g), was also markedly improved in PAC water extract- treated group as compared to the diabetic control group. Taken together, these data suggest that PAC water extract may have a potential as a antidiabetic agent in type 2 diabetes mellitus.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.561-569
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• 2021

Diabetic nephropathy is a major and representative complication of type 2 diabetes. Hyperglycemia increases the incidence of diabetic nephropathy, and induces kidney inflammation, thereby causing renal fibrosis, which is an important factor in the pathogenesis of diabetic nephropathy. This study investigated the effects of blackcurrant extract (BLC), which has been implicated in diabetic nephropathy in db/db mice, on glomerular fibrosis and renal dysfunction. The results showed that BLC consumption in type 2 diabetic db/db mice ameliorated diabetes-related metabolic disorders, such as insulin resistance and renal dysfunction, and significantly attenuated renal inflammation and renal fibrosis in diabetic nephropathy. In conclusion, these findings suggest that BLC consumption may help prevent renal fibrosis, inflammation, and consequent diabetic nephropathy.

• Journal of Life Science
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• v.27 no.9
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• pp.1052-1058
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• 2017

Gelidium amansii shows antioxidant and anti-obesity effects; however, the effect on postprandial blood glucose levels is not known. The objective of the present study was to investigate the inhibitory effect of Gelidium amansii extract (GAE) on carbohydrate-digesting enzymes and its ability to alleviate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Gelidium amansii was extracted with 80% ethanol and concentrated for use in this study. The ${\alpha}-glucosidase$ and ${\alpha}-amylase$ inhibition assays were performed using the colorimetric method. ICR normal and STZ-induced diabetic mice were orally administered GAE (300 mg/kg body weight) or acarbose (100 mg/kg body weight) alone or soluble starch (2 g/kg body weight). Blood samples were taken from the tail vein at 0, 30, 60 and 120 min. Our results indicated that GAE markedly inhibited ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities with $IC_{50}$ values of $0.099{\pm}0.009mg/ml$ and $0.178{\pm}0.038mg/ml$, respectively, and was a more effective inhibitor than acarbose, the positive control. Further, the postprandial blood glucose levels of STZ-induced diabetic mice in the GAE-administered group were significantly lower than those of control group mice (p<0.05). Moreover, the area under the curves (AUC) significantly decreased with GAE administration in STZ-induced diabetic mice (p<0.05). These results indicate that GAE may be effective in decreasing postprandial blood glucose levels by inhibiting carbohydrate-digesting enzymes such as ${\alpha}-amylase$ and ${\alpha}-glucosidase$. Therefore, GAE could be used as a potential functional food for alleviating postprandial hyperglycemia.