• The Journal of Korean Medicine
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• v.16 no.2 s.30
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• pp.337-347
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• 1995

The purpose of this study was to investigate the effect of pretreatment with Saegchinyanghyoltang(SYT) on the serum lipid composition and atherosclerotic index in streptozotocin(STZ)-induced diabetic rats. SYT 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 SYT, triglyceride and lipid levels were significantly lower compared with those of STZ -induced diabetic rat group without STZ. 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 SYT pretreatment Pretreatment with SYT significantly increased the activities of serum lipase compared to the STZ-treated group.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.437-442
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• 1996

Hypoglycemic effect of Tabebuia avellandae was investigated in the streptozotocin(STZ)-induced diabetic rats. Diabetes was induced in male Sprague-Dawley rats by injections of STZ (45 mg/kg, i.v.). Rats weighing 200-250 g were divided into 6 groups: normal, STZ-control, hexane fr., CHCl$_3$fr., BuOH fr. and $H_2O$ fr. group. Normal and STZ-control rats received 3% Tween 80 only. Four groups of diabetic rats were administered orally at doses of 100, 400, 300 and 400 mg/kg/day of hexane, CHC1$_3$, BuOH and $H_2O$ fr. respectively. Fractions were administered orally to the rats for 7 days after STZ injection. All rats were anesthetized with ether, blood samples were taken by cardiac puncture for clinical chemistry and the rats were killed by exsanguination. Liver, kidney, heart and spleen were removed, weighed and analyzed. We measured glucose, protein, cholesterol and triglyceride levels in the plasma and glycogen, cholesterol and triglyceride levels in liver. The extent of blood glucose decrement in rats administered $H_2O$ fraction was greater than that in the STZ-control rats. The serum cholesterol and triglyceride levels were significantly lowered by administration of $H_2O$ fraction compared with those of STZ-control group. Treatment of rats with Tabebuia avellandae fractions caused decreases in STZ-induced elevation of cholesterol and triglyceride. Liver triglyceride level was significantly lowered hexane and BuOH fraction group compared with STZ-control group. These results suggest that $H_2O$ fraction of Tabebuia avellandae has the hypoglycemic action against STZ-induced diabetic rats.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.112-124
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• 1998

The purpose of this study was to investigate the effect of Brousson etiae fructus (BF) on the urethral nitrite level and the urethral nitric oxide synthase (NOS) activity in streptozotocin (STZ) induced diabetic rats. In vitro, the urethral NOS activity was not noted in the level of Dose of extract prepared from BF. In vivo, the urethral NOS activity was increased in normal rats and STZ induced diabetic rats by dose and term of extract prerared from BF. The the NOS activity decreased in STZ induced diabetic rats was increased as highly as norma1 group by the extract of BF The level of urethral nitrite and glutathione was increased too. But the level of urethral lipid peroxide increased in STZ induced diabetic rats was decreased as lowly as normal group by the extract of BF. In conclusion, the extract of BF can restore erectile dysfunction of STZ induced diabetic rats.

• Advances in Traditional Medicine
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• v.5 no.2
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• pp.144-149
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• 2005

The present study was designed to investigate the hypoglycaemic and hypolipidaemic activities of Qurs-e-Ziabetus 16 (QZ-16) in Streptozotocin (STZ) induced diabetic rats. QZ-16, a polypharmaceutical herbomineral formulation developed on the principles of Unani medicine is used for non-insulin dependent diabetes mellitus (NIDDM). The elevated levels of fasting blood glucose, serum levels of cholesterol, triglycerides and urea observed in rats treated with STZ (55 mg/kg body wt.) were significantly reduced by the treatment of QZ-16 (240 mg/kg, p.o.) and gliclazide (30 mg/kg, p.o.). The reduced HDL cholesterol levels were also increased by the QZ-16 and gliclazide treatments in the STZ induced diabetic rats. These data show that QZ-16 has hypoglycaemic, hypolipidaemic properties in STZ induced diabetic rats.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.375-382
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• 1999

Growing evidence indicates that enhanced generation or actions of nitric oxide (NO) are implicated in the pathogenesis of hypertension in spontaneously hypertensive rats and diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. We investigated whether inducible nitric oxide synthase (iNOS) expression in STZ-induced diabetic rats is responsible for the alterations of vascular reactivity. Diabetic state was confirmed 28 days after injection of STZ (i.p) in rats by measuring blood glucose. In order to evaluate whether short term (4 weeks) diabetic state is related with altered vascular reactivity caused by iNOS expression, isometric tension experiments were performed. In addition, plasma nitrite/nitrate (NOx) levels and expression of iNOS in the lung and aorta of control and STZ-treated rats were compared by using Griess reagent and Western analysis, respectively. Results indicated that STZ-treated rats increased the maximal contractile response of the aorta to phenylephrine (PE), and high $K^+,$ while the sensitivity remained unaltered. Endothelium-dependent relaxation, but not SNP-mediated relaxation, was reduced in STZ-treated rats. Plasma nitrite/nitrates are significantly increased in STZ-treated rats compared to controls. The malondialdehyde (MDA) contents of liver, serum, and aorta of diabetic rats were also significantly increased. Furthermore, nitrotyrosine, a specific foot print of peroxynitrite, was significantly increased in endothelial cells and smooth muscle layers in STZ-induced diabetic aorta. Taken together, the present findings indicate that enhanced release of NO by iNOS along with increased lipid peroxidation in diabetic conditions may be responsible, at least in part, for the augmented contractility, possibly through the modification of endothelial integrity or ecNOS activity of endothelium in STZ-diabetic rat aorta.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.159-167
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• 2009

Objectives : So-Dang-Hwan (SDH) is used as a traditional treatment of diabetes in oriental clinics in Korea. This study aimed to evaluate antidiabetic effect of SDH in streptozotocin (STZ)-induced diabetic rats. Methods : Diabetes was induced by i.p. injection of STZ (45 mg/kg) to Sprague-Dawley rats. Experimental animals (eight per group), were treated by oral administration of SDH (60 mg/kg body weight) and glibenclimide (1 mg/kg), a known antidiabetic drug for comparison, during 5 weeks. To veridy the effect of SDH, the levels of glucose, triglyceride, insulin, BUN and creatinine were measured in sera from experimental diabetic rats, and an oral glucose tolerance test (OGTT) was also performed. Results : SDH prevented body weight loss in diabetic rats. SDH exhibited at termination, a significant reduction in blood glucose levels in STZ-induced diabetic rats. SDH significantly reduced serum creatinine levels toward the normal levels. The OGTT results showed a significant improvement in glucose tolerance in rats treated with SDH. Conclusions : These data indicate that SDH treatment may improve glocose homeostasis in STZ-induced diabetes.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.489-496
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• 2000

This study was conducted to investigate the effects of streptozotocin-induced (STZ) diabetes on insulin-like growth factor-I (IGF-I), insulin-like growth factor binding proteins (IGFBPs), and IGF-I carrier proteins in serum, liver, and kidney. The levels of total and free IGF-I were measured by radioimmunoassay (RIA). The patterns of IGFBPs were determined by western ligand blotting (WLB) analysis. The profiles of IGF-I carrier proteins in serum were determined by column chromatography. The levels of total and free IGF-I in serum were lower in STZ-induced diabetic rat than normal rat (p<0.01). Similarly, the levels of total IGF-I in liver was lowered in STZ-induced diabetic rats. On the other hand, the levels of total IGF-I in kidney were increased in STZ-induced diabetic rats compared with normal rats (p<0.01). In serum and liver from STZ-induced diabetic rats, the amount of IGFBP-3 was decreased and the amount of IGFBP-2 was increased compared with normal rats. There was a not difference in amount of IGFBP-4 in serum between STZ-induced diabetic rats and normal rats. The serums of normal rats have higher 150kDa carrier proteins than in STZ-induced diabetic rats, whereas, most of 50kDa carrier proteins were found in STZ-induced diabetic rats. These results demonstrate that in STZ-induced diabetic rats, IGF-I/IGFBPs system that included functional bioactivity was changed in serum as well as tissues, and these changes may play an important role in pathogenesis of diabetes.

• Journal of Life Science
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• v.16 no.5
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• pp.767-772
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• 2006

This study was to investigate the effect of betaine on the hypoglycemia and hepatoprotection of streptozotocin(STZ)-induced diabetic rats. Male Sprague-Dawley rats weighing around 280 g were randomly assigned to the three experimental groups: a healthy normal group and two groups with STZ-induced diabetes and fed either control diet or betaine diet. Betaine given to the STZ-diabetic rats had significant effect in lowering the serum glucose concentrations compared to the STZ-diabetic rats. The alanine aminotransferase (AST) and aspartate aminotransferase (ALT) activities and triglyceride contents in serum were dramatically higher in the STZ-diabetic rats, but these increases in relation to diabetes also decreased in the STZ-diabetic rats fed betaine. However, the total-cholesterol concentration in the STZ-diabetic rats was even increased by betaine. The morphology of the pancreatic islets in the normal rats showed a typical round form, but most of the islets in the STZ-diabetic rats showed severe morphological alterations by being markedly destroyed. However, the islet morphology of STZ-diabetic rats given betaine mostly maintained a normal rounded appearance. The present study strongly suggests that the administration of betaine showed a moderate hypoglycemic effect by protecting the pancreatic beta-cells by morphological examination from STZ-induced destruction.

• Journal of Nutrition and Health
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• v.32 no.7
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• pp.767-774
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• 1999

This study was carrid out to examine a part of the mechanism for the etiology of diabetic complications. Thirty normal and forty streptozotocin(STZ)-induced diabetic rats were used as the animal models. Animals were sacrificed at the time points of 3 days, 1, 2, 4 and 6 weeks after STZ-injection and time course in body weight and organ weight, the levels of blood glucose, plasma lipid patterns, and atherogenic index were measured during 6 weeks. The STZ-diabetic animals showed 63% survival rate and fsting blood glucose levels of the diabetic animals measured in the range of 230-410mg/dL during the experimental period. The body weigh of diabetic animals decreased significantly throughout the experimental period and the relative weights of organs to body weight were significantly higher than the normal control ones. The enlargement of the kidney in the diabetic animals was especially remarkable. Plasma triglyceride concentration in diabetic rats substancially increased from the first week of onset of diabetes mellitus and maintained higher levels than the control ones throughout the whole experimental period. The plasma total cholesterol level and atherogenic index in the diabetic rats were significantly higher than the normal ones from the third day after STZ injection and showed a gradual increase with the duration of the disease. Throughout the experiment, the diabetic rats consistently showed a slightly lower HDL-cholesterol level compared to the normal animals. From the results of this study, it appears that the significant changes in blood lipid pattern in STZ-diabetic animals start from the first week after STZ injection.

• Natural Product Sciences
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• v.22 no.3
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• pp.175-179
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• 2016

The aim of this study was to evaluate the anti-diabetic effects of the water extract of Lespedeza cuneata (LCW) using rat insulinoma (RIN) m5F cells and streptozotocin (STZ)-induced diabetic rats. The effect of LCW on the protection of pancreatic beta cells was assessed using MTT assay, and nitric oxide production was assessed using Griess reagent. STZ-induced diabetic rats were treated with 100 and 400 mg/kg body weight of LCW for 5 weeks. In results, LCW significantly protected cytokine-induced toxicity and NO production, and increased insulin secretion in RINm5F cells. LCW significantly decreased serum blood glucose, thiobarbituric acid reactive substances (TBARS), blood urea nitrogen (BUN) and advanced glycation end products (AGEs) levels, and renal fibronectin expression in STZ-induced diabetic rats. Also, LCW effectively improved BW loss in STZ-induced diabetic rats. Thus, our results suggest that LCW has a beneficial effect on cytokine-induced pancreatic beta cell damage and biomarkers of diabetic complication in hyperglycemic rats.