• Biomolecules & Therapeutics
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• 제26권2호
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• pp.201-209
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• 2018

G protein-coupled receptor 119 (GPR119) is expressed in the pancreas and gastrointestinal tract, and its activation promotes insulin secretion in the beta cells of the pancreatic islets as well as the secretion of glucagon-like peptide-1 (GLP-1) in intestinal L cells, consequently improving glucose-stimulated insulin secretion. Due to this dual mechanism of action, the development of small-molecule GPR119 agonists has received significant interest for the treatment of type 2 diabetes. We newly synthesized 1,2,4-triazolone derivatives of GPR119 agonists, which demonstrated excellent outcomes in a cyclic adenosine monophosphate (cAMP) assay. Among the synthesized derivatives, YH18968 showed cAMP=2.8 nM; in GLUTag cell, GLP-1secretion=2.3 fold; in the HIT-T15 cell, and insulin secretion=1.9 fold. Single oral administration of YH18968 improved glucose tolerance and combined treatment with a dipeptidyl peptidase 4 (DPP-4) inhibitor augmented the glucose lowering effect as well as the plasma level of active GLP-1 in normal mice. Single oral administration of YH18968 improved glucose tolerance in a diet induced obese mice model. This effect was maintained after repeated dosing for 4 weeks. The results indicate that YH18968 combined with a DPP-4 inhibitor may be an effective therapeutic candidate for the treatment of type 2 diabetes.

• 셀메드
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• 제4권4호
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• pp.27.1-27.5
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• 2014

Picrorhiza kurroa Royle ex Benth. (Scrophulariaceae) is a traditional Ayurvedic herb known as Kutki. It is used as a remedy for diabetes by tribes of North Eastern Himalayan region of India. Present study was conducted to explore the mechanism of antidiabetic activity of standardized aqueous extract of Picrorhiza kurroa (PkE). PkE (100 and 200 mg/kg/day) was orally administered to streptozotocin induced diabetic rats, for 14 consecutive days. Plasma insulin levels were measured and pancreas of rat was subjected to histopathological investigations. Glucose transporter type 4 (GLUT-4) protein content in the total membrane fractions of soleus muscle was estimated by Western blot analysis. Plasma insulin level was significantly increased along with concomitant increase in GLUT-4 content of total membrane fractions of soleus muscle of diabetic rats treated with extract. There was evidence of regeneration of ${\beta}$-cells of pancreatic islets of PkE treated group in histopathological examinations. PkE increased the insulin-mediated translocation of GLUT-4 from cytosol to plasma membrane or increased GLUT-4 expression, which in turn facilitated glucose uptake by skeletal muscles in diabetic rats.

• Journal of Ginseng Research
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• 제44권4호
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• pp.619-626
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• 2020

Background: The effects of diol-ginsenoside fraction (Diol-GF) and triol-ginsenoside fraction (Triol-GF) from Korean Red Ginseng on the development of type 1 diabetes (T1D) were examined in diabetes-prone biobreeding (DP-BB) rats that spontaneously develop T1D through an autoimmune process. Methods: DP-BB female rats were treated with Diol-GF or Triol-GF daily from the age of 3-4 weeks up to 11-12 weeks (1 mg/g body weight). Results: Diol-GF delayed the onset, and reduced the incidence, of T1D. Islets of Diol-GF-treated DP-BB rats showed significantly lower insulitis and preserved higher plasma and pancreatic insulin levels. Diol-GF failed to change the proportion of lymphocyte subsets such as T cells, natural killer cells, and macrophages in the spleen and blood. Diol-GF had no effect on the ability of DP-BB rat splenocytes to induce diabetes in recipients. Diol-GF and diol-ginsenoside Rb1 significantly decreased tumor necrosis factor α production, whereas diol-ginsenosides Rb1 and Rd decreased interleukin 1β production in RAW264.7 cells. Furthermore, mixed cytokine- and chemical-induced β-cell cytotoxicity was greatly inhibited by Diol-GF and diol-ginsenosides Rc and Rd in RIN5mF cells. However, nitric oxide production in RAW264.7 cells was unaffected by diol-ginsenosides. Conclusion: Diol-GF, but not Triol-GF, significantly delayed the development of insulitis and T1D in DP-BB rats. The antidiabetogenic action of Diol-GF may result from the decrease in cytokine production and increase in β-cell resistance to cytokine/free radical-induced cytotoxicity.

• 약학회지
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• 제55권4호
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• pp.301-308
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• 2011

Diabetes has been one of major health risks in industrialized countries. AMP-activated protein kinase (AMPK) has been focused as a novel therapeutic target for the treatment of metabolic syndromes, because AMPK increases glucose uptake through independent insulin signal pathway. In this study, we investigated the anti-diabetic effect of Angelica gigas Nakai extract (AGNEX), a mixture of decursin and decursinol angelate (53 : 47), decursin and decursinol angelate on blood glucose, glucose transport (GLUT) and AMPK expression levels in streptozotocin (STZ)-induced diabetic rats. To induce diabetes, 50 mg/kg of STZ was injected via i.v. route and AGNEX 2 mg/kg (STZ+AG), decursin 2 mg/kg (STZ+D), decursinol angelate 2 mg/kg (STZ+DA), and metformin 100 mg/kg (STZ+M) were administered orally for 21 days. STZ+DA group showed a significant decrease in fasting blood glucose levels compared to the other groups. Decursinol angelate significantly upregulated expression of glucose transporter 4 (GLUT4) and phosphorylation of AMPK (p-AMPK) in skeletal muscle of rats. In pancreas of rats, decursinol angelate significantly increased expression of GLUT2 through down-regulation of p-AMPK. In addition to the result of pancreatic islets morphology, AGNEX, decursin, decursinol angelate, and metformin treated group recovered ${\beta}$-cell damage by hyperglycemia. These results indicate that decursinol angelate might be a potential anti-diabetic agent and AGNEX could be useful in the treatment of diabetes mellitus.

• 약학회지
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• 제50권6호
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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.

• Nutrition Research and Practice
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• 제13권5호
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• pp.367-376
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• 2019

BACKGROUND/OBJECTIVE: The blue honeysuckle berry (Lonicera caerulea var. edulis L.) is a small deciduous shrub belonging to the Caprifoliaceae family that is native to Russia, China, Japan, and Korea. The berry of this shrub is edible, sweet and juicy and is commonly known as the blue honeyberry (BHB). This study examined the anti-diabetic potential of BHB on high-fat-diet-induced mild diabetic mice. The hypoglycemic, and nephroprotective effects of the 12-week oral administration of blue honeyberry extract were analyzed. MATERIALS/METHODS: The hypoglycemic effects were based on the observed changes in insulin, blood glucose, and glycated hemoglobin (HbA1c). Furthermore, the changes in the weight of the pancreas, including its histopathology and immunohistochemical investigation were also performed. Moreover, the nephroprotective effects were analyzed by observing the changes in kidney weight, its histopathology, blood urea nitrogen (BUN), and serum creatinine levels. RESULTS: The results showed that the high-fat diet (HFD)-induced control mice showed a noticeable increase in blood glucose, insulin, HbA1c, BUN, and creatinine levels. Furthermore, growth was observed in lipid droplet deposition related to the degenerative lesions in the vacuolated renal tubules with the evident enlargement and hyperplasia of the pancreatic islets. In addition, in the endocrine pancreas, there was an increase in the insulin-and glucagon-producing cells, as well as in the insulin/glucagon cell ratios. On the other hand, compared to the HFD-treated mice group, all these diabetic and related complications were ameliorated significantly in a dose-dependent manner after 84 days of the continuous oral administration of BHBe at 400, 200 and 100 mg/kg, and a dramatic resettlement in the hepatic glucose-regulating enzyme activities was observed. CONCLUSIONS: By assessing the key parameters for T2DM, the present study showed that the BHBe could act as a potential herbal agent to cure diabetes (type II) and associated ailments in HFD-induced mice.

• 한방비만학회지
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• 제21권2호
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• pp.59-68
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• 2021

Objectives: We investigated the effects of Clean-DM4 (C-DM4), a polyherbal extract consisting of Coptidis Rhizoma, Salviae Miltiorrhiza Radix, and Cinnamomi Cortex on high fat diet (HFD)-induced obesity and diabetes in mice. Methods: The C57BL/6 mice (6 weeks) were fed a HFD for 8 weeks and then administrated with C-DM4 extract at 500 mg/kg (p.o.) once daily for 4 weeks. The changes of body weights, calorie intakes, and fasting blood glucose (FBG) levels were measured in mice. The serum levels of glucose, insulin, total cholesterol, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured in mice by enzyme-based assay. It was also observed the histological changes of pancreas, liver, and fat tissues with hematoxylin and eosin (H&E) staining. Results: The increase of calorie intakes and FBG levels in HFD-induced obesity mice was significantly decreased by oral administration of C-DM4 extract. C-DM4 extract administration was significantly reduced the increased levels of glucose, insulin, total cholesterol, AST, and ALT in obesity mice. In addition, C-DM4 extract inhibited lipid droplet accumulation in liver tissues of obesity mice, hyperplasia of pancreatic islets, and enlargement of adipocytes in adipose tissues. Conclusions: Our study indicates that C-DM4 extract could help improve obesity and to prevent diabetes progression.

• Journal of Nutrition and Health
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• 제47권6호
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• pp.394-402
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• 2014

본 연구는 황칠나무의 부위별 추출물의 항당뇨효능을 평가하기 위해, 황칠나무의 잎과 줄기의 열수추출물과 에탄올추출물을 분리하여 항산화능과 당뇨질환 개선효능을 측정하였다. 그 결과, total polyphenol과 total flavonoid의 농도는 DLW에서 가장 높게 나타났으며, 다음으로 DLE, DSW, DSE 순서로 나타났다. 또한, DPPH 소거능은 DLW가 대부분의 농도에서 가장 높게 나타났으며, DLE는 $500{\mu}g/mL$의 농도에서 가장 높은 DPPH 소거능을 나타내었다. 항산화능이 우수한 DLW와 DLE를 선정하여 STZ로 유도된 당뇨모델동물에 2주간 투여하여 항당뇨 효능을 분석하였다. 그 결과, 체중은 STZ/vehicle 처리군이 급격히 감소하였으나 STZ/DLW와 STZ/DLE 처리군에서 서서히 감소하였다. 혈당량은 STZ/vehicle 처리군에서 급격히 증가하였으며, STZ/DLW 처리군과 STZ/DLE 처리군에서만 유의적인 감소를 나타내었다. 그러나, 혈청 내 인슐린의 농도는 STZ/vehicle 처리군에 비하여 STZ/DLW와 STZ/DLE 처리군에서 증가하였으며, 특히 STZ/DEL-200 처리군에서 가장 높은 농도를 나타내었다. 이러한 변화는 췌장의 조직학적 변화와 면역염색의 결과에서도 동일하게 관찰되었다. 더불어, 뇨당 농도는 STZ/vehicle 처리군에서 급격히 증가하였으며, 오직 STZ/DLW-200 처리군과 STZ/DLE-200 처리군에서만 유의적으로 감소하였다. 이러한 결과는 황칠나무의 잎의 열수추출물과 에탄올추출물은 우수한 항산화효능과 베타세포의 사멸을 억제함으로서 당뇨질환을 개선하는 효능이 있음을 제시하고 있으며, 특히, 200 mg/kg의 농도가 우수한 효능을 나타내는 농도임을 제시하고 있다.

• 약학회지
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• 제53권5호
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• pp.286-292
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• 2009

In this study, we investigated the anti-obese activity of HPJ extract in C57BL/6J mice. The C57BL/6J mice were randomly divided into five groups: normal control group (Con), high fat diet control group (HFD), treatment groups with HPJ at 125 mg/kg (HPJ125), 250 mg/kg (HPJ250), or 500 mg/kg (HPJ500). To induce an obesity, mice were fed by a high fat diet for 6 weeks, and mice were administered with HPJ extract once a day for 8 weeks. At the end of treatment, we examined the effect of HPJ extract on body weight, plasma lipid, and lipogenic enzymes. HPJ extract was found to lower whole body and epididymal adipose tissue weights and lowered plasma levels of glucose, insulin, triglyceride (TG), total cholesterol (TC), non-esterified fatty acid (NEFA) and leptin, compared to those in HFD group. Histological analyses of the liver and fat tissues of mice treated with HPJ extract revealed significantly decreased number of lipid droplets and decreased size of adipocytes compared to the HFD group. In addition, HPJ extract preserved the morphological integrity of pancreatic islets. To elucidate an action mechanism of HPJ extract, Western blot and RT-PCR were performed using epididymal adipose tissues. HPJ extract up-regulated the levels of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylasse (ACC). HPJ extract also attenuated lipogenic gene expressions of sterol regulatory element-binding protein $1{\alpha}$ (SREBP$1{\alpha}$), fatty acid synthase (FAS), sterol-CoA desaturase 1 (SCD1) and glycerol-3-phosphate acyltransferase (GPAT) in dose-dependent manners. In contrast, expressions of lipolytic genes such as peroxisome proliferator-activated receptor-$\alpha$ (PPAR-${\alpha}$) and CD36, and fatty acid $\beta$-oxidation gene, carnitine palmitoyltransferase-1 (CPT-1) were increased. These results suggest that HPJ extract ameliorates obesity through inhibiting synthesis of lipogenic enzymes as well as stimulating fatty acid oxidation resulting from activation of AMPK, and HPJ extract could be developed as a potential therapeutic agent for obese patients.

• Journal of Acupuncture Research
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• 제22권1호
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• pp.1-11
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• 2005

한약복합처방(SHP)의 약침 및 경구투여가 STZ으로 유발된 흰쥐의 당뇨병과 항산화능에 미치는 영향을 연구한 결과 다음과 같은 결론을 얻었다. 1. In vitro 에서 SHP은 ${\alpha}$-glucosidase 저해 및 DPPH 라디칼 소거 활성을 나타냈으며, t-BHP에 의한 신장 피질 조직에서의 지질 과산화 생성을 억제하였다. 2. SHP은 대조군에 비해 STZ에 의한 혈청 중 insulin 함량 저하를 유의성있게 증가시켰으며, 혈청 중 glucose 함량변화에 있어서도 유의성 있게 감소시켰다. 3. SHP은 대조군에 비해 STZ에 의해 상승된 혈청 중 triglyceride 함량을 유의성있게 감소시켰고, 혈청 중 total cholesterol 함량을 감소시키는 경향을 보였으나 유의성은 없었다. 4. STZ 투여로 인해 혈청 내 지질과산화물의 함량이 증가되었으며 SHP의 약침 및 경구투여로 감소되는 경향을 보였으나 유의성은 없었다. 5. STZ에 의해 증가된 catalase 활성은 SHP에 의해 감소되는 경향을 보였으나 유의성은 없었으며, glutathione 활성 역시 SHP에 의해 감소되는 경향을 보였으나 유의성은 없었다.