• Journal of Life Science
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• v.23 no.6
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• pp.825-831
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• 2013

The aim of this study was to investigate the effects of induced diabetes by streptozotocin (STZ) administration on gene expression of proinflammatory cytokines in adipose tissue of C57/BL6 mice fed either a normal diet (ND) or a high-fat diet (HFD). Four diabetic mice groups (16- or 26-week-old mice fed either ND or HFD) and four control groups of age and diet matched non-diabetic mice were used. By real-time PCR, gene expression levels of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and monocyte chemoattractant protein-1 (MCP-1) were examined in adipose tissue. The results demonstrated that gene expression of TNF-${\alpha}$ was significantly or marginally increased in STZ induced diabetic mice groups compared with non-diabetic groups. On the other hand, MCP-1 gene expression tended to be decreased in diabetic mice compared with non-diabetic controls. Especially, MCP-1 expression level in 16w diabetic mice on HFD was about 26% of that in age and diet matched non-diabetic controls (p<0.001). In addition, MCP-1 gene expression in adipose tissue was correlated with plasma insulin levels (p=0.0002). These results suggest that gene expression of proinflammatory cytokines in adipose tissue is differentially regulated in mouse models of diabetes. The basic data in this study will be useful for elucidating basic mechanisms of inflammatory state and increased expression of proinflammatory cytokines in adipose tissue in obesity, insulin resistance, and diabetes.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.75-79
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• 2008

Nerve growth factor (NGF) is a protein plays a major role in the development and maintenance of central and peripheral nervous system. Recent data suggest that reduced availability of NGF may play a significant role in the pathogenesis of diabetic $polyneuropathy.^{1)}$ In our previous study, steroidal saponin from Liriope platyphylla showed neurotrophic effect by stimulation of NGF synthesis and activation of tyrosine kinase $signaling.^{2)}$ In this study, we examined the neurotrophic effect of Liriope platyphylla (LP); which was from Mylyang(MYL) and Cheongyang(CHE), and Ophiopogon japonicus (CHI) on in vitro and in vivo model for the comparison of their NGF induction. We quantitatively analyzed spicatoside A in the LP and CHI by HPLC. And we investigated the correlation between the contents of spicatoside A and NGF induction efficacy on PC 12 cells and mouse serum. These results suggest that spicatoside A may enhance NGF induction in animal model.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.259-265
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• 2015

Momordica charantia, commonly known as bitter melon, has interesting pharmacological activities such as anticancer, antiviral, antibacterial, anti-inflammatory, analgesic, and antioxidant. As supported by recent scientific reports on the beneficial effects of M. charantia, it is one of the most promising functional plants for diabetes today. In this study, we fermented the bitter melon with lactic acid bacteria and investigated the capability of controlling diabetic conditions by decreasing the blood glucose levels. After extracting the fermented bitter melon with hot water or ethanol, we tested several biological activities using mouse models. When we tested the efficacy of the glycemic control, the extracts of fermented bitter melon significantly lowered the blood glucose levels of the alloxan-induced diabetic mice. We also found that the lactic acid bacteria-fermented bitter melon protected liver damages from the treatment of alloxan monohydrates and maintained low levels of triglycerides and high levels of HDL cholesterol in these mouse models. These results suggest that our approach on fermenting bitter melon and the extracts of fermented bitter melon could lead to the possibility of the development of functional foods that contain the effectiveness of controlling blood glucose and lipid levels as well as preventing liver damages.

• Development and Reproduction
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• v.24 no.3
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• pp.231-239
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• 2020

Many benefits of silk protein fibroin (SPF) have been suggested in biomedical applications; and notably, significant SPF effects have been observed for metabolic syndromes that are directly linked to insulin resistance, such as type 2 diabetes mellitus (T2DM). Based on our previous findings, we believe that SPF from spiders exhibits outstanding glucose-lowering effects in diabetic BKS.Cg-m+/+Lepr^db mice. In order to evaluate the dietary effects of SPF in diabetic animals, we generated several lines of transgenic rice (TR) that expresses SPF, and the feeding of TR-SPF to diabetic animals decreased blood glucose levels, but did not change insulin levels. Western blot analyses of hepatic proteins showed that AMP-activated protein kinase (AMPK) expression and phosphorylation both decreased in TR-SPF-fed groups, compared with controls. This finding suggests that the glucose-lowering effects in this diabetic animal model might be AMPK-independent. In contrast, six-transmembrane protein of prostate 2 (STAMP2) was upregulated after TR-SPF exposure. Together with STAMP2, the Akt protein phosphorylation increased after TR-SPF exposure, which indicates that STAMP2 leads to Akt phosphorylation and thus increases insulin sensitivity in hepatocytes. Importantly, the hepatic steatosis that was seen in the liver of diabetic mice was remarkably alleviated in TR-SPF-fed mice. Hepatocytes that were immunopositive for STAMP2 were overwhelmingly observed in hepatic tissues from TR-SPF-fed mice compared to the control. Taken together, these results suggest that feeding diabetic mice with TR-SPF upregulates STAMP2 expression and increases Akt phosphorylation in hepatic tissues and thus potentially alleviates insulin resistance and hepatic steatosis.

• Journal of Periodontal and Implant Science
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• v.53 no.1
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• pp.54-68
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• 2023

Purpose: The purpose of this study was to determine whether metformin (MF) could alleviate the expresssion of reactive oxygen species (ROS) and improve the osteogenic ability of bone marrow mesenchymal stem cells derived from diabetic rats (drBMSCs) in vitro, and to evaluate the effect of MF on the ectopic osteogenesis of drBMSCs in a nude mouse model in vivo. Methods: BMSCs were extracted from normal and diabetic rats. In vitro, a cell viability assay (Cell Counting Kit-8), tests of alkaline phosphatase (ALP) activity, and western blot analysis were first used to determine the cell proliferation and osteogenic differentiation of drBMSCs that were subjected to treatment with different concentrations of MF (0, 50, 100, 200, 500 µM). The cells were then divided into 5 groups: (1) normal rat BMSCs (the BMSCs derived from normal rats group), (2) the drBMSCs group, (3) the drBMSCs + Mito-TEMPO (10 µM, ROS scavenger) group, (4) the drBMSCs + MF (200 µM) group, and (5) the drBMSCs + MF (200 µM) + H₂O₂ (50 µM, ROS activator) group. Intracellular ROS detection, a senescence-associated β-galactosidase assay, ALP staining, alizarin red staining, western blotting, and immunofluorescence assays were performed to determine the effects of MF on oxidative stress and osteogenic differentiation in drBMSCs. In vivo, the effect of MF on the ectopic osteogenesis of drBMSCs was evaluated in a nude mouse model. Results: MF effectively reduced ROS levels in drBMSCs. The cell proliferation, ALP activity, mineral deposition, and osteogenic-related protein expression of drBMSCs were demonstrably higher in the MF-treated group than in the non-MF-treated group. H₂O₂ inhibited the effects of MF. In addition, ectopic osteogenesis was significantly increased in drBMSCs treated with MF. Conclusions: MF promoted the proliferation and osteogenic differentiation of drBMSCs by inhibiting the oxidative stress induced by diabetes and enhenced the ectopic bone formation of drBMSCs in nude mice.

• The Korea Journal of Herbology
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• v.24 no.4
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• pp.55-62
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• 2009

Objectives : This study was designed to investigate the effects of an aqueous extract from Buddleja officinalis Maxim (ABO) on vascular dysfunction in low-density lipoprotein receptor deficient (LDLr KO) mice. Methods : Present study showed that LDLr KO mice were fed a high fat diet consisting of 60 kcal% fat, with or without 200 mg/day/kg ABO of diet, for 14 weeks. Results : High fat diet-LDLr KO mice were treated with ABO were completely normalized by lowering glucose. ABO reduced intima/media thickness in a high fat diet-LDLr KO mice without affecting plasma cholesterol and triglyceride levels. ABO caused endothelium-dependent relaxation in the acetylcholine-precontracted aorta of high fat diet-LDLr KO mice. ABO increased eNOS expression, while decreased cell adhesion molecules expression in high fat diet-LDLr KO mice. Conclusions : In conclusion, chronic treatment with ABO improved hyperglycemia and endothelium-dependent vascular relaxation as well as exhibited anti-inflammatory effect in diabetic atherosclerotic mouse model, independent of effects on plasma lipids.

• Archives of Pharmacal Research
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• v.29 no.8
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• pp.666-676
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• 2006

Gangliosides are widely distributed in mammalian cells and play important roles in various functions such as cell differentiation and growth control. In addition, diabetes and obesity cause abnormal development of reproductive processes in a variety of species. However, the mechanisms underlying these effects, and how they are related, are not fully understood. This study examined whether the differential expression of gangliosides is implicated in the abnormal follicular development and uterine architecture of streptozotocin (STZ)-induced and db/db diabetic mice. Based upon the mobility on high-performance thin-layer chromatography, mouse ovary consisted of at least five different ganglioside components, mainly gangliosides GM3, GM1, GD1a and GT1b, and diabetic ovary exhibited a significant reduction in ganglioside expression with apparent changes in the major gangliosides. A prominent immunofluorescence microscopy showed a dramatic loss of ganglioside GD1a expression in the primary, secondary and Graafian follicles of STZ-induced and db/db diabetic mice. A significant decrease in ganglioside GD3 expression was also observed in the ovary of db/db mice. In the uterus of STZ-induced diabetic mice, expression of gangliosides GD1a and GT1b was obviously reduced, but gangliosides GM1, GM2 and GD3 expression was increased. In contrast, the uterus of db/db mice showed a significant increase in gangliosides GM1, GD1a and GD3 expression. Taken together, a complex pattern of ganglioside expression was seen in the ovary and uterus of normoglycemic ICR and $db/^+$ mice, and the correspoding tissues in diabetic mice are characterized by appreciable changes of the major ganglioside expression. These results suggest that alterations in ganglioside expression caused by diabetes mellitus may be implicated in abnormal ovarian development and uterine structure.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.57-69
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• 2007

Objectives : Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications have shown that oxidative stress might play a major role. Therefore, many methods have been tried to regulate free oxygen radicals for treating diabetes and its complications. Ojung-hwan, composed of five crude herbs, has been considered effective for treating symptoms of aging. In male ob/ob mouse of severe obesity, hyperinsulinemia and hyperlipidemia, which are features of NIDDM, the hyperglycemic activities and mechanisms of Ojung-hwan were examined. Methods : Mice were grouped and treated for 5 weeks as follows. Both the lean (C57/BL6J black mice) and diabetic (ob/ob mice) control groups received standard chow. The experimental groups were fed a diet of chow supplemented with 30 and 90 mg Ojung-hwan per 1 kg of body weight for 14 days. The effects of Ojung-hwan extract on the ob/ob mice were observed by measuring the serum levels of glucose, insulin, lipid components, and the kidney levels of superoxide anion radical (${\cdot}\;O{_2}{^-}$), MDA+HAE, GSH/GSSG ratio, and also the enzyme activities involved in polyol pathway. Results : Ojung-hwan lowered the levels of serum glucose and insulin in a dose-dependent manner. Total cholesterol, triglyceride and free fatty acid levels decreased, while the HDL-cholesterol level increased, in Ojung-hwan treated groups. Renal aldose reductase and sorbitol dehydrogenase activities increased in the ob/ob mice, whereas they were inhibited in the Ojung-hwan treated groups. Ojung-hwan inhibited the generation of ${\cdot}\;O{_2}{^-}$ in the kidney. Finally, MDA+HAE levels increased and GSH/GSSG ratio decreased in the ob/ob mice, whereas they improved in the Ojung-hwan treated groups. Conclusions : Ojung-hwan showed antidiabetic and antihyperlipidemic activities by regulating theactivities of polyol pathway enzymes, scavenging reactive oxygen species and reducing the MDA+HAE levels in the ob/ob mice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.584-587
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• 2002

It has been suggested that oxidative stress may play an important role in the pathogenesis of diabetic complications. The purpose of this study was to examine the oxidative stress of streptozotocin(STZ) in the cultured mouse cerebral neurons and the preventing effect of vitamin E and and Benincasae Semen(BS) on STZ-induced neurotoxicity. Cytotoxic effect of STZ and neuroprotective effect of antioxidant and BS were performed by MTT assay. 30 μM STZ decreased cell viability in dose-and time-dependent mannner, and vitamin E and BS diminished STZ-induced neurotoxicity in these cultures. From above the results, STZ has toxic effect. and antioxidants, vitamin E or herb extract of BS is very effective against STZ-induced neurotoxicity in cultured cerebral neurons of neonatal mouse.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.195-201
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• 1995

In this study we wanted to investigate the effect of taurine supplement on the lipid peroxide formation and the activities of glutathione(GSH) dependent enzyme in diabetic model mice. We induce type I diabetes mellitus with alloxan injeciton in ICR mice and type II with high calorie diet in genetically hyperglycemic KK mice. Taurine was given in drinking water at the level of 5%(w/v) for seven days. In type I diabetic model, the malondialdehyde(MDA) of liver and islet significantly increased compared to control group and they significantly decreased by taurine supplement. In type II diabetic model, the concentration of MDA was not changed by taurine supplement. The activities of GSH-peroxidase(GPX) of liver and islet increased in type I diabetic group while decreased in type II. GPX activities were not changed by taurine supplement in the liver of both types but increased in the islet of type II. Taurine supplement has no effect on the activities of GSH S-transferase(GST) in both types. From these results, we suggest that taurine supplement protect against lipid peroxide formation in diabetic model of type I.