• Journal of Nutrition and Health
• /
• v.36 no.3
• /
• pp.239-244
• /
• 2003

This study investigated the in vivo insulin function of Polygonatum odoratum in normal and diabetic male Sprague-Dawley rats. Diabetes mellitus was induced by an i.p. injection of streptozotocin. Normal and diabetic rats were assigned to the diet groups of the control basal diet and Polygonatum odoratum diet. The animals were fed the diet and water ad libitum for 15 days. Initial and final body weights, total food intake and serum glucose and insulin levels were measured. An insulin suppression test was performed to elucidate the insulin function in the peripheral tissues. The results showed that the final serum glucose levels significantly decreased in the diabetic rats on the Polygonatum odoratum diet compared with the diabetic rats on the control diet. The final serum insulin levels were increased in the diabetic rats on the Polygonatum odoratum diet compared with the diabetic rats on the control diet. The in vivo function of the insulin increased in the diabetic rats on the Polygonatum odoratum compared with the diabetic rats on the control diet. These data indicate that Polygonatum odoratum may be beneficial in improving the in vivo insulin function in streptozotocin-induced diabetic rats.

• The Korean Journal of Physiology and Pharmacology
• /
• v.9 no.5
• /
• pp.305-314
• /
• 2005

Diabetes mellitus is associated with vascular complications, including an impairment of vascular function and alterations in the reactivity of blood vessels to vasoactive substances in various vasculature. In the present study, the authors have observed endothelin-B ($ET_B$) receptor agonist-induced relaxation in precontracted mesenteric arterial segments from streptozotocin (STZ)-induced diabetic rats, which was not shown from control rats or in other arterial segments from diabetic rats. Accordingly, the goal of this study was to investigate in what way STZ-induced diabetes altered reactivity of the mesenteric arterial bed and to examine the causal relaxation, if any, between this $ET_B$ receptor-mediated relaxation and endothelial paracrine function, especially nitric oxide (NO) production. The relaxation induced by $ET_B$ agonists was not observed in mesenteric arteries without endothelium. The relaxation to $ET_B$ agonists was completely abolished by pretreatment with BQ788, but not by BQ610. $N_{\omega}-nitro-L-arginine$ methyl ester and soluble guanylate cyclase inhibitors, methylene blue or LY83583 significantly attenuated the relaxant responses to $ET_B$ agonists, respectively. When the expression of eNOS and iNOS was evaluated on agarose gel stained with ethidium bromide, the expression of eNOS mRNA in diabetic rats was significantly decreased, but the expression of iNOS was increased compared with control rats. Furthermore, the iNOS-like immunostaining was densely detected in the endothelium and slightly in the arterial smooth muscle of diabetic rats, but not in control rats. These observations suggest that $ET_B$ receptor may not play a role in maintaining mesenteric vascular tone in normal situation. However, the alterations in $ET_B$ receptor sensitivity were found in diabetic rats and lead to the $ET_B$ agonist-induced vasorelaxation, which is closely related to NO production. In the state of increased vascular resistance of diabetic mesenteric vascular bed, enhanced NO production by activation of iNOS could lead to compensatory vasorelaxation to modulate adequate perfusion pressure to splanchnic area.

• Journal of Society of Preventive Korean Medicine
• /
• v.10 no.1
• /
• pp.75-93
• /
• 2006

Rhus verniciflua Stokes(RVS) has been widely used as a food and traditional herbal medicine in Korea. RVS has been reported that the extract from its wood and fruit has strong antioxidant activity and anticancer effect but there is little information on Lacca Sinica Exsiccata(LSE), the resin of RVS, as a medicinal use. The aim of this study was to evaluate the antidiabetic effect of ethanol-eluted extract of LSE on streptozotocin(STZ) - induced diabetic rats. Diabetes was induced in male Sprague-Dawley rats with STZ injection. Oral administration of LSE extract(50mg or 100mg/kg of body weight/day) was given to diabetic group. During 4 weeks of experiment, diabetic rats showed significant weight loss and decreasing feed efficiency ratios(FER) compared with normal rats, while the diabetic group orally fed with LSE extract showed a trend of decreasing weight loss and a significant increase of FER(p<0.05). In 4 weeks after induction of diabetes, diabetic rats showed an increase in weight of liver, kidney and heart, whereas the diabetic rats administered with LSE extract showed a reduction in the weight of heart. Blood glucose level was decreased in diabetic rats treated with LSE extract, but it was not statistically significant. Glutamic oxaloacetic transaminase, Glutamic pyruvate transaminase and total cholesterol levels were lower in the diabetic group treated with LSE extract than in untreated diabetic group, but not significant. These results present that LSE may partly have antidiabetic effect and may protect against the development of diabetic heart complications resulting from impaired glucose metabolism.

• Korean Journal of Community Nutrition
• /
• v.4 no.1
• /
• pp.103-110
• /
• 1999

The purpose of this study was to determine the effects of taurine supplementation and taurine depletion on blood glucose and blood lipid concentrations in insulin-treated diabetic rats. Four groups of Sprague-Dawley male rats were fed the purified diet for 3 weeks ; nontaurine-supplemented diabetic rats(E0), nontaurine-supplemented diabetic rats with insulin treatment(E0＋I), 1% taurine-supplemented diabetic rats with insulin treatment(E1＋I) and taurine-depleted diabetic rats with insulin treatment(EA＋I). Diabetes was induced by streptozotocin injection(50mg/kg B.W.). Isophane insulin was given subcutaneously into the abdominal wall of the diabetic rats(4 unit/rat/day). E1＋I were supplemented with 1% taurine in drinking water. To induce taurine depletion, EA＋I were treated with 5% $\beta$-alanine in drinking water. E1＋I had significantly higher body weight compared to that of E0. The food intakes of E1＋I and E0＋I were significantly decreased compared to that of E0. There was no sigfniciant difference in food intake between E1＋I and E0＋I. The water intake of rats was significantly different among the groups ; E0>E0＋I>E1＋I>EA＋I. The urine volume of E0 was significantly increased compared to those of insulin-treated goups. The blood glucose concentration of E0 was significantly increased compared to those of insulin-treated groups. In the oral glucose tolerance test(OGTT), E0＋I and E1＋I had significantly lower blood blucose concentrations compared to E0 after 30 min. Also EA＋I had significantly lower bloodglucose concentrtion compared to E0 and E0＋I. The plasma total cholesterol and LDL-cholesterol concentratons of EA＋I were significantly incrased compared to those of other groups. Therefore, it may be suggested that tuarine supplementation is useful for insulin-dependent diabetes in order to prevent diabetic complications suchas cardiac vascular diseases.

• Journal of Life Science
• /
• v.20 no.12
• /
• pp.1750-1757
• /
• 2010

This study was designed to evaluate the anti-diabetic effects of Buan mulberries by using an insulin-dependent diabetes mellitus animal model. Several studies have shown that mulberries have metabolism-improving, antioxidant, and lipid-lowering properties in rats with streptozotocin (STZ)-induced diabetes. In this study, Sprague-Dawley male rats were randomly assigned to 1 normal control group and 5 STZ-induced diabetes groups: rats that had STZ-induced diabetes and did not receive any agents (diabetic group; negative control), rats that had STZ-induced diabetes and received insulin (insulin group; positive control), rats that had STZ-induced diabetes and received 0.5% mulberry extract (0.5% mulberry group), rats that had STZ-induced diabetes and received 1.0% mulberry extract (1.0% mulberry group), and rats that had STZ-induced diabetes and received 2.0% mulberry extract (2.0% mulberry group). Mulberry extracts were administered to the diabetic animals for 4 weeks. The rats that received mulberry extracts showed lower body weights and insulin levels, as well as higher kidney weights, blood glucose levels, urine quantities, and water intake in comparison with the normal controls. Further, the insulin concentrations in the mulberry-fed animals were higher than those in the diabetic group, and the kidney weights, blood glucose levels, urine quantities, and water intake in the mulberry-fed animals were lower than the corresponding values in the diabetic controls. These results suggest that mulberry may be an effective functional food to prevent diabetes-related complications.

• Journal of Periodontal and Implant Science
• /
• v.47 no.5
• /
• pp.339-350
• /
• 2017

Purpose: The purpose of this study was to determine the critical diabetes duration in a streptozotocin (STZ)-induced diabetic rat calvarial defect model for experimentation regarding bone regeneration by evaluating the association between diabetes duration and bone healing capacity through histological and radiographic analyses. Methods: Experimental diabetes was induced in 50 of 60 rats by an STZ injection. The rats were divided into 5 groups, including a control group (group 1), according to diabetes durations of 0, 2, 4, 6, and 8 weeks, respectively. Eighteen rats survived: 4 in group 1, 4 in group 2, 4 in group 3, 5 in group 4, and 1 in group 5. Calvarial defects were created at 0, 2, 4, 6, and 8 weeks after STZ injection in groups 1-5. Cone-beam computed tomography scanning was performed at baseline and at 5 and 7 weeks after surgery. The rats were sacrificed 7 weeks after surgery, followed by histological evaluation. Results: The voxel gray values (VGVs) of group 1 and group 2 increased, whereas the VGVs of group 3 and group 4 decreased starting 5 weeks after surgery, although this trend did not reach statistical significance between groups. On the reconstructed 3-dimensional images and based on an analysis of histological features, groups 1 and 2 showed apparent bone regeneration, while groups 3-5 showed very limited bone regeneration. Conclusions: The critical diabetes duration in an STZ-induced diabetic rat calvarial defect model for experimentation regarding bone regeneration was between 2 and 4 weeks. It is suggested that researchers who use STZ-induced diabetic rats wait for more than 2 weeks following diabetes induction before placing implants or conducting bone regeneration studies to allow definite disturbances in bone healing to emerge.

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.4
• /
• pp.309-318
• /
• 2015

Alcohol consumption increases the risk of type 2 diabetes. However, its effects on prediabetes or early diabetes have not been studied. We investigated endoplasmic reticulum (ER) stress in the pancreas and liver resulting from chronic alcohol consumption in the prediabetes and early stages of diabetes. We separated Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a type-2 diabetic animal model, into two groups based on diabetic stage: prediabetes and early diabetes were defined as occurrence between the ages of 11 to 16 weeks and 17 to 22 weeks, respectively. The experimental group received an ethanol-containing liquid diet for 6 weeks. An intraperitoneal glucose tolerance test was conducted after 16 and 22 weeks for the prediabetic and early diabetes groups, respectively. There were no significant differences in body weight between the control and ethanol groups. Fasting and 120-min glucose levels were lower and higher, respectively, in the ethanol group than in the control group. In prediabetes rats, alcohol induced significant expression of ER stress markers in the pancreas; however, alcohol did not affect the liver. In early diabetes rats, alcohol significantly increased most ER stress-marker levels in both the pancreas and liver. These results indicate that chronic alcohol consumption increased the risk of diabetes in prediabetic and early diabetic OLETF rats; the pancreas was more susceptible to damage than was the liver in the early diabetic stages, and the adaptive and proapoptotic pathway of ER stress may play key roles in the development and progression of diabetes affected by chronic alcohol ingestion.

• Korean Journal of Food Science and Technology
• /
• v.32 no.5
• /
• pp.1206-1212
• /
• 2000

This study was conducted to know whether Gamiyookmijihwangtang(GY) which is Yookmijihwang added with Liriopis tuber, Anemarrhenae rhizoma and Phellodendri cortex can remedy the overt diabetes in diabetes-prone BB(BBDP) rats. The rats were given GY through the mother from the fetal stage until birth. After birth they received GY through breast feeding until 20 days old. From 21 days old which is the beginning of the weaning period 60 BB rats(30 males and 30 females) were divided into 2 experimental groups(BBDP and BBDP-GY) and placed individually in metabolic cages. BBDP was the control group which didn't receive any GY and BBDP-GY received 16 mL/㎏ B.W./day of GY until 120 days old. The antidiabetic effects of GY were characterized by the clinical features such as polyurea, polydipsia, hyperglycaemia and the rapid loss of body weight. Body weight, water consumption, urine volume and blood glucose level showed no signs of impending diabetes but after onset there were big changes in those parameters. The onset of diabetes was delayed and the incidence of diabetes was also much decreased with GY but after onset there were no beneficial effects from it.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.5
• /
• pp.908-913
• /
• 1997

The purpose of this study was to investigate phospholipase $A_{2}$ activity and lipid peroxidation I streptozotocin induced diabetic rats. Sprague-Dawley male rats weighting-Dawley male rats weighting 300$\pm$10gm were randomly assigned to normal and STZ-induced diabetic group. Diabetes was induced by intravenous injection of 55mg/kg of STZ in sodium citrate buffer(pH 4.3). Animals were sacrificed at the 6th day of diabetic states. Body weight gains were lower in DM group. Phosphatidylcholine hydrolysis in liver was not significantly different between two groups, whereas phosphatidylethanolamine hydrolysis in liver was increased by 69% in DM group comparing with that of normal group. Liver microsomal phospholipase $A_{2}$ activity and level of TBARS was increased by 91%, 109% in DM group compared with that of normal group, respectively. The present results indicate that phospholipase $A_{2}$ activity is specific to PE hydrolysis, leading to lipid peroxidation process in STZ induced diabetic rats.

• Journal of Acupuncture Research
• /
• v.20 no.3
• /
• pp.1-14
• /
• 2003

Objective : The aim of the study was to investigate the preventive effect of Acanthopanax senticosus(AS) aqua-acupuncture into Sinsu(BL23) of the multiple low-does strepozotocin(STZ)-induced diabetic rats. Methods : The experimental animals were divided into 4 groups : normal group of rats, control group of multiple low-does STZ-induced diabetic rats, NSAA group with 0.4ml normal saline(NS) aqua-acupunctured subcutaneously into Sinsu in multiple low-does STZ-induced diabetic rats, and ASAA group with 0.4ml of 20% AS aqua-acupunctured subcutaneously into Sinsu in multiple low-does STZ-induced diabetic rats. Each of AS and NS aqua-acupuncture was done subcutaneously into both loci of Sinsu taking turns everyday for 3 weeks. Thereafter the levels of serum glucose, body weight, index of kidney hypertrophy, urine glucose, urinary albumin excretion, creatinine clearance, mesangial cell and TGF-${\beta}1$ expression in glomeruli and tubular cells were measured on the determined day. Conclusions : 1. Both ASAA and NSAA groups decreased the serum glucose levels in multiple low-dose STZ-induced diabetic rats as compared to the cintrol group, and ASAA group showed more significant decreases than NSAA group. 2. Both ASAA and NSAA groups prevented the development of diabetes in multiple low-dose STZ-induced diabetic rats as compared to the control group, and ASAA group prevented more markedly the development of diabetes than NSAA group. 3. Both ASAA and NSAA groups prevented the reduction of body weight in multiple low-dose STZ-induced diabetic rats as compared to the control group, and ASAA group showed the same as the normal group. 4. Both ASAA and NSAA groups did not show any changes of the creatinine clearance in multiple low-does STZ-induced diabetic rats. 5. Both ASAA and NSAA groups prevented the excretion of urinary glucose and albumin in multiple low-dose STZ-induced diabetic rats as compared to the cintrol group, and ASAA group showed more significant prevention than NSAA group. 6. Both ASAA and NSAA groups prevented the expansion of glomerular cells and the protein expression of transforming growth factor-${\beta}1$ in multiple low-dose STZ-induced diabetic rats as compared to the cintrol group, and ASAA group prevented more significantly than NSAA group.