• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.246-251
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• 2009

This study examined the possible hypoglycemic effects Angelica gigas Naki extracts in streptozotocin-induced diabetic rats(STZ+50%, STZ+100% EtOH and STZ+water). The studies showed that administration of the Angelica gigas Naki extract decreased high blood glucose levels(more than 300 mg/$d{\ell}$) to a normal level(104 mg/$d{\ell}$) in the STZ+50% EtOH group. Liver glucokinase levels were significantly increased in STZ+50% EtOH and STZ+100% EtOH groups compared to the STZ group. Moreover, the liver acetyl CoA carboxylase level was significantly increased in STZ+50% EtOH, STZ+100% EtOH and STZ+water groups compared to the STZ group. These results suggest that the Angelica gigas Naki extract in the STZ+50% EtOH group exerted an ameliorable effect and can be used as an anti-diabetic substance, either as a dietary supplements or as a new drug.

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.213-217
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• 2009

This study was done to investigate the antioxidative effect of polygoni radix in Streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45 mg/kg dissolved in citrate buffer. The ethanol extract of Polygoni radix was orally administrated once a day for 7 days. The contents of Total cholesterol, triglyceride (TG) were significantly decreased in Polygoni radix treated STZ-sample group compared with to the those of STZ-control group. The hepatic cytosolic activities of glutathione-s-transferase (GST), superoxide dismutase (SOD) were significantly increased, Also the content of glutathione (GSH) was incresaed in Polygoni radix treated STZ-sample group compared with to the those of STZ-control group. but the content of malondialdehyde (MDA) and the hepatic cytosolic activity of Catalase (CAT) were decreaed but not statistical significant. These results indicated that ethanol extract of polygoni radix was effective for the antidxidative in the STZ-induced diabetic rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.306-311
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• 1991

The purpose of this study was to investigate the effect of pretreatment with nicotinamide on the serum lipid composition and atherosclerotic index in streptozotocin ( STZ ) - induced diabetic rats. Nicotinamide pretreatment in STZ-induced diabetic rats inhibited the rise of serum glucose concentration. Serum total lipids and triglyceride levels in the STZ-induced diabetic rats were significantly higher than those in the control group. But in the group pretreated with nicotin-amide, triglyceride and lipid levels were significantly lower compared with those of STZ-induced diabetic rat group without nicotinamide. However, the serum phospholipid levels were not statistically different among treatment groups. In the STZ-induced diabetic group, the serum total cholesterol, VLDL, LDL-cholesterol levels and atherosclerotic index were higher and HDL-cholesterol level was lower compared to the control group. However, these changes were prevented by nicotinamide pretreatment. Pretreatment with nicotinamide significantly increased tile activities of serum lipase compared to the STZ-treated group. Aminotranferase (ALT, AST) activities were not significantly different in any of the groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.203-208
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• 1991

The present study was undertaken in order to elucidate the effects of pretreatment with nicotinamide on changes in the hepatic metabolizing enzyme system inducted by streptozotocin (STZ). In rats, STZ(50mg/kg) administered by tail vein caused a significant rise in hepatic aniline hydroxylase and a decrease in aminopyrine N-demethylase when compared to control (p<0.05). Pretreatment with nicotinamice inhibited these effects (p<0.05). Similarly, STZ induced changes in hepatic microsomal cytochrome P-450 activity were inhibited by pretreatment with nicotinamide (p<0.05). However, changes in UDP-glucuronyl transferase and sulfortransferase activity were not significantly different(p>0.05). Pretreatment with nicotinamide also prevented STZ induced increases in glutathion S-tranferase activity when compared to the control(p<0.05). There results suggest that nicotinamide pretreatment suppresses STZ-induced changes in the hepatic metabolizing enzyme system.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.300-308
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• 2004

This study was done to investigate the antidiabetic effect of Glechoma hederacea LINNAEUS in Streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45 mg/kg dissolved in citrate buffer. The methanol extract of Glechoma hederacea was orally administrated once a day for 6 days. The contents of serum glucose, triglyceride (TG), total cholesterol and Atherogenic Index (Al) were significantly decreased, but high density lipoprotein (HDL)-cholesterol and HDL-cholesterol/total cholesterol ratio (HTR) were significantly increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic lipid peroxide and activity of catalase were decreased, but content of glutathione as well as activities of glutathione-S-transferase and superoxide dismutase were increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-6-phosphate dehydrogenase, glucokinase were significantly increased, but activity of glucose-6-phosphatase was decreased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. These results indicated that methanol extract of Glechoma hederacea would have antidiabetic effect in STZ-induced diabetic rats.

• YAKHAK HOEJI
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• v.36 no.1
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• pp.80-86
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• 1992

Streptozotocin (STZ) is a naturally occurring nitrosoamide used extensively to produce diabetes in experimental animals. Our previous study has demonstrated that i.v. administraton of streptozotocin induces significant red blood cell hemolmysis in rats. Since it has been reported that the highest concentration of STZ is found in the liver, the effect of STZ in freshly isolated rat hepatocytes has been investigated. STZ treatment (10 mM) did not cause significant loss of viability throughout 4 hour incubation, while high dose of STZ (300 mM) to hepatocytes resulted in complete cell death within 3 hours. Addition of 40 mM glucose to incubation medium did not potentiate STZ-induced hepatotoxicity, suggesting that STZ-induced hyperglycemia in vivo did not affect its hepatotoxicity. To investigate the mechanixm of the toxicity, intracellular total glutathione level was determined. Tratment with 10 mM STZ which was not toxic to hepatocytes led to complete depletion of intracellular glutathione level within 1 hour incubation. These results suggest that STZ-induced hepatotoxicity may be independent on the intracellular glutathione depletion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1267-1272
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• 1998

In order to investigate the preventive and therapeutic of royal jelly on diabetes, the levels of blood glucose and serum lipids as well as the number of blood cells were determined in streptozotocin(STZ) diabetic rats. Rats were divided into seven groups. The RJ group was administered royal jelly and the STZ group was treated with streptozotocin to induce diabetes. To determine the preventive effect, diabetes was induced after administration of royal jelly for 2 weeks in group RS1/RS2. In group SR1/SR2 diabetic rats were administered royal jelly for 2 weeks to investigate the therapeutic effect. After 3 weeks, the body weight was reduced in STZ and SR1 groups and food intake was increased in the STZ, RS1 and SR1 groups. The blood glucose level was similar to the control group in the RJ, RS1 and RS2 groups and there was no effect in the other groups. The total lipid and triglyceride level were lower in the SR1 group as compared to STZ, and the total cholesterol level was higher in the STZ group. The index of atherogenesis was lower in the RJ and SR1 groups compared to the normal group. The number of red blood cells and hemoglobin was higher in the RJ and SR1 groups and the number of white blood cells was higher in the RJ and SR2 groups.

• Food Science and Preservation
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• v.21 no.4
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• pp.549-559
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• 2014

This study investigated the hypoglycemic effects of mulberry leaf (M), green tea (G), and a mixture of mulberry leaf and green tea (MG) in rats with streptozotocin-induced diabetes. Male Sprague-Dawley rats were divided into the non-diabetic (N) and diabetic groups. The experimental animals were divided into four groups and fed the following for four weeks: a normal diet (N), the STZ+normal diet (STZ), the STZ+5% mulberry leaf (STZ-M), STZ+5% green tea (STZ-G), and the STZ+5% mixture of mulberry leaf and green tea (STZ-MG). The whole blood glucose level of the STZ-M, STZ-G and STZ-MG groups significantly decreased compared to the STZ group two weeks later. The serum glucose and fructosamine, and urine glucose levels in the STZ-M, STZ-G and STZ-MG groups were lower than in the STZ group. The levels of serum insulin were higher in the STZ-M, STZ-G and STZ-MG groups than in the STZ group. However, serum glucose, fructosamine and insulin levels, and urine glucose levels were not significantly different among the STZ-M, STZ-G and STZ-MG groups. These results indicate that mulberry leaf, green tea, and their mixture help prevent or attenuate the progression of diabetes in rats with STZ-induced diabetes.

• Nutritional Sciences
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• v.6 no.4
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• pp.209-215
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• 2003

This research was performed to investigate the effects of the supplementation of multi-extracts of mori folium (MF) and of exercise on blood lipid profiles and tissue differentiation in streptozotocin (STZ)-induced diabetic rats. The animal groups consisted of a normal-control group, a STZ-control group, three STZ-induced diabetic groups supplemented ad libitum with various amounts of MF extracts (MF-720, MF-360, and MF-180 groups), and a STZ-induced diabetic group supplemented with MF-360 combined with exercise; eight male Sprague-Dawley rats, 4 weeks old, were assigned to each experimental group and were raised in the laboratory for a 10 week experimental period. The MF supplementation group showed a significant reduction in levels of serum total cholesterol and triglyceride compared to the STZ-control group. HDL-cholesterol levels were significantly increased in the MF supplementation group compared to STZ-control group. The ratio of HDL-cholesterol to total cholesterol was significantly higher in MF supplementation group compared to the STZ-control group. The Atherogenic Index (AI) values in the MF supplementation groups were found to be significantly lower than in the STZ-control group. Serum AST and ALT levels were significantly reduced in the MF-supplementation groups compared to the STZ-control group. Total cholesterol level in the liver tissue was significantly decreased in the MF-360 group and in the MF-360 + exercise group compared to the STZ-control group. In immunohistochemical staining of the pancreatic islets of the MF-supplemented groups, a significantly higher number of insulin-immunoreactive cells were observed compared to the STZ-control group. In the MF supplementation groups, Bowman's capsules were clearly observed as hypertrophy of the glomeruli was not obvious. In the MF supplementation groups, a relative reduction in the hypertrophy of the basement membrane of the glomeruli and a significant reduction in the mesangium were observed compared to the STZ-control group. The results of this study suggest that supplementation of MF has beneficial effect in improving plasma lipid and tissue metabolism in streptozotocin-induced rats.

• Journal of Community Nutrition
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• v.2 no.2
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• pp.164-169
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• 2000

The purpose of this study was to examine the effect of taurine supplementation time on the activity of the enzymes metabolizing lipid peroxide in the liver of streptozotocin(STZ)-induced diabetic rats, Sprague-Dawley male rats were fed the purified diet for 7 weeks. They were supplemented with or without 1% taurine in drinking water before or after STZ injection or during all experimental procedure. In comparison to diabetic group without taurine, glucose-6-phosphatase(G6Pase) activity was decreased in diabetic group supplemented with taurine before STZ injection, and it was increased in diabetic group supplemented with taurine after STZ injection, but the difference was not significant. Glutathione S-transferase(GST) activity was significantly increased by the injection of STZ. However, the GST activities of diabetic groups exposed to taurine after STZ injection or during all experimental procedure were significantly decreased. Glutathione peroxidase(GPx) activities was significantly decreased by STZ injection. However, only in diabetic group supplemented with taurine before STZ injection, GPx activities was not decreased by the STZ injection. These results suggest that taurine supplementation may change the activities of GSH-related enzymes metabolizing lipid peroxide in the liver of streptozotocin(STZ)-induced diabetic rats and that may be helpful for the prevention of diabetic complication.