• Archives of Pharmacal Research
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• v.25 no.3
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• pp.306-312
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• 2002

Aldose reductase, the key enzyme of the polyol pathway, is known to play important roles in the diabetic complication. The inhibitors of aldose reductase, therefore, would be potential agents for the prevention of diabetic complications. To evaluate active principles for the inhibition of aldose reductase from the rhizomes of Belamcanda chinensis, twelve phenolic compounds were isolated and tested for their effects on rat lens aldose reductase. As a result, isoflavones such as tectorigenin, irigenin and their glucosides were found to show a strong aldose reductase inhibition. Tectoridin and tectorigenin, exhibited the highest aldose reductase inhibitory potency, their $IC_{50}$ values, being $1.08{\times}10^{-6}{\;}M{\;}and{\;}1.12{\times}10^{-6}{\;}M$, respectively, for DL-glyceraldehyde as a substrate. Both compounds, when administered orally at 100 mg/kg for 10 consecutive days to streptozotocin-induced diabetic rats, caused a significant inhibition of sorbitol accumulation in the tissues such as lens, sciatic nerves and red blood cells. Tectorigenin showed a stronger inhibitory activity than tectoridin. From these results, it is suggested that tectorigenin is attributed to be a promising compound for the prevention and/or treatment of diabetic complications.

• The Korea Journal of Herbology
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• v.21 no.3
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• pp.75-81
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• 2006

Objectives : The present study was carried out to investigate the beneficial effect of Coicis Semen extract(CSe) on streptozotocin(STZ)-induced diabetic nephropathy rats. CSe was given to rats with oral administration. Methods : The experimental animals were divided into 3 groups : normal group of rats, control group of STZ-induced diabetic rats, sample group with CSe treatment. Experimental diabetes was induced by the injection of STZ(60 mg/kg) to the rat via the peritoneum. The effects of CSe on STZ-induced diabetic nephropathy were observed by measuring the serum level of creatinine, BUN and uric level of glucose. Kidney level of lipid peroxidation and the activities of reduced glutathione(GSH) were also examined Results : STZ-induced increase of serum creatinine was lowered by CSe treatment, but BUN and uric level of glucose did not show significant changes. CSe oral administration showed statistical decrease of lipid peroxidation in renal cortical tissues, but it has no effect on the activities of GSH. Conclusion : CSe treatment showed protective effect on rat diabetic nephropathy model, but action mechanism of the effect was still not dear. We thought to be concerned with anti-oxidative stress.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.739-745
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• 2006

Changes in the levels of analytes in the blood and urine of a rodent animal model were taken as a measure of the hypoglycemic effects of a diet containing fermented chaga mushroom. These studies were conducted using the genetically manipulated diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The effects of 8-week long diets that included either fermented (FCM) or non-fermented (CM) chaga mushroom powder (5% in the diet) on the OLETF rat were compared to the normal diet fed OLETF rat and the non-diabetic Long-Evans Tokushima Otsuka (LETO) rat. Hypoglycemia was tracked by measuring serum and urine concentrations of glucose, insulin, fructosamine, and leptin. Serum and urine levels of glucose, fructosamine, and leptin in the OLETF rats were higher than in LETO rats when fed normal diets but insulin levels did not differ between the two animal groups. The FCM rats were characterized by dramatically low levels of serum glucose and leptin in the OLETF rats whereas the levels of fructosamine and urine glucose trended lower in response to FCM. The serum leptin level in the CM-fed OLETF rat was also lower than that in the normal diet fed OLETF control. Serum concentrations of insulin in the OLETF rats were higher following FCM or CM feeding compared to the normal diet. These observations imply that (a) a dietary supplement of fermented chaga mushroom may contribute to a hypoglycemic effect in the OLETF rat, and (b) the increased blood insulin concentration following 8 weeks of an FCM diet may be important to the noted improvement in hyperglycemia.

• Imaging Science in Dentistry
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• v.34 no.2
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• pp.81-89
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• 2004

Purpose: To investigate the histopathological changes in the temporomandibular joint in streptozotocin-induced diabetic rat following irradiation. Materials and Methods : Sprague-Dawley rats weighing about 250 gm were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control group were injected with citrate buffer only. After 5 days, the head and neck region of the rats in diabetic-irradiated group were irradiated with single absorbed dose of 10 Gy. The rats were killed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimen including the temporomandibular joint were sectioned and observed using a histopathological method. Results : In the diabetic group, severe bone resorption in the mandibular condyle was observed throughout the period of experiment. Necrosis of bone marrow and trabeculae was observed at 28 days after diabetic state. Atrophy and fibrosis in the retrodisca] tissue was gradually progressed during the time of the experiment. In the diabetic-irradiated group, severe bone resorption in the mandibular condyle was observed during the early experimental phases, but regeneration of bone marrow was initiated at ]4 days after diabetic state and irradiation. A]so, calcification of abnormal trabeculae was observed at 28 days after diabetic state and irradiation. The retrodisca] tissue was degenerated in the early experimental phases, but it had been gradually regenerated during the experimental time. Conclusion: This experiment suggests that bone resorption and degeneration in the mandibular condyle are caused by the induction of diabetes, and abnormal bone formation is induced after irradiation in diabetic state.

• BMB Reports
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• v.41 no.10
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• pp.710-715
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• 2008

This study investigated the effect of Phellodendri Cortex extract on hyperglycemia and diabetic nephropathy in streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were divided into normal control (NC), diabetic control (DC), and diabetic treatment with Phellodendri Cortex extract (DP). Over a 4-week experimental period, Phellodendri Cortex extract was administered orally at 379 mg/kg BW/day. The final fasting serum glucose level, urine total protein level, and relative left kidney weight in the DP group were significantly lower than the DC group. Renal XO and SOD activities in the DP group were significantly lower than the DC group and renal CAT activity in the DP group was significantly higher than the DC group. Tubular epithelial change was reduced in the DP group compared to the DC group. These results indicated that Phellodendri Cortex can reduce glucose level and prevent or retard the development of diabetic nephropathy in streptozotocin-induced diabetic rats.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.195-202
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• 1993

Oxidative modification of cellular proteins and lipids may play a role in the development of diabetic complications. Diabetic cardiomyopathy has been suggested to be caused by the intracellular $Ca^{2+}$ overload in the myocardium, which is partly due to the defect of calcium transport of the cardiac sarcoplasmic reticulum (SR). In the present study, the possible mechanism of the functional defect of cardiac SR in diabetic rats was studied. Both of the maximal $Ca^{2+}$ uptake and the affinity for $Ca^{2+}$ were decreased in the diabetic rat SR in comparison with the control. To investigate whether the functional defect of the cardiac SR in streptozotocin-induced diabetic rat is associated with the oxidative changes of cardiac SR proteins, the carbonyl group content and glycohemoglobin levels were determined. The increase in carbonyl group content of cardiac SR (2.30 nmols/mg protein, DM; 1.78, control) and in glycohemoglobin level $(13{\sim}17%,\;DM;\;3{\sim}5%,\;control)$ were observed in the diabetics. The extent of increase in calcium transport by phospholamban phosphorylation was greater in the diabetic cardiac SR membranes than that in the control. The phosphorylation levels of phospholamban, as determined by SDS-PAGE and autoradiography with $[{\gamma}^{32}P]ATP$, were increased in diabetic cardiac SR. These results suggest that the impaired cardiac SR function in diabetic rat could be a consequence of the less-phosphorylation of phospholamban in the basal state, which is partly due to the depleted norepinephrine stores in the heart. Furthermore, the oxidative damages in cardiac SR membranes might be one of the additional factors leading to the diabetic cardiomyopathy.

• The Journal of Korean Medicine
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• v.27 no.1 s.65
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• pp.47-56
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• 2006

The present study was carried out to investigate the preventive effect of Epimedii Herba combined Samgijiwhang-Tang(SJTE) on streptozotocin(STZ)-induced diabetic nephropathy. SJTE was given to rats with oral administration. The experimental animals were divided into normal group of rats, control group of STZ-induced diabetic rats, and sample group with SJTE administration. Experimental diabetic nephropathy was induced by the injection of STZ(60mg/kg) to the rat via the peritoneum. The effect of SJTE on STZ-induced diabetic nephropathy was observed by measuring the serum level of insulin, glucose, creatinine and BUN. Urine secretion of albumin for 24 hours and urine level of glucose measures too. Anti-oxidative stress of STZ administration in living body was estimated by measuring lipid peroxide in cortex of kidneys. STZ induced increase of serum glucose. creatinine, urine albumin secretion and renal cortical lipid peroxidation were lowered by SJTE administration. In conclusion, the SJTE treatment showed protective effect on rat diabolic nephropathy model, and action mechanism of the effect was thought to be concerned with internal glucose metabolism.

• Korean Journal of Pharmacognosy
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• v.22 no.4
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• pp.225-232
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• 1991

The hypoglycemic and metabolic effects of Commelina communis L. extract were investigated in alloxan-diabetic rats. The increased blood glucose level in the diabetic rats was significantly lowered and the loss of body weight in the diabetic rats was recovered with the treatments of the crude extract. Administration of the extract elicited the significant increase of glucose-6-phosphate dehydrogenase activity and liver weight which were decreased in the alloxan-treated rat serum and liver. On the other hand, the kidney weight and glucose-6-phosphate dehydrogenase activity were increased in the alloxan treated rat kidney and were potentiated by the treatment of the extract. In both liver and kidney, together with serum, alkaline phosphatase and ATPase activities were increased in the alloxan diabetic rats and were not recovered, rather potentiated by the administration of the extract.

• The Journal of Internal Korean Medicine
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• v.35 no.4
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• pp.519-531
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• 2014

Objectives: Diabetic nephropathy is the most common cause of end stage renal disease. Transforming growth factor (TGF)-${\beta}1$, type IV collagen, advanced glycation end-products (AGEs), and angiotensin II type 1 receptor (AT1) are the main factors of diabetic nephropathy. We investigated the effects of Prunus on renal function and histopathological changes of diabetic nephropathy rat model induced by unilateral nephrectomy and streptozotocin. Methods: Diabetes was induced in male Sprague-Dawley rats ($290{\pm}10g$) by injecting streptozotocin (55 mg/kg) into the tail vein after unilateral nephrectomy. Rats were divided into 3 groups (n=6): normal, control, and Prunus. After 8 weeks of oral administration of Prunus extract on the Prunus group from 3 days after streptozotocin injection, we checked weight, 24 hrs urine, blood biochemistry and renal tissue to evaluate renal function and histopathological changes by examining parameters including albuminuria, BUN, creatinine, cholesterol, low density lipoprotein (LDL), triglyceride, TGF-${\beta}1$, type IV collagen, AGEs, and AT1. We also measured mRNA expression of TGF-${\beta}1$, type IV collagen, AGEs, and AT1 by Real Time polymerase chain reaction (RT-PCR). Results: Prunus decreased the amount of 24 hrs proteinuria, and inhibited histopathological changes of diabetic nephropathy including the expression and accumulation of TGF-${\beta}1$, type IV collagen and AGEs which could promote development of diabetic nephropathy. Prunus also inhibited mRNA expression of TGF-${\beta}1$, type IV collagen. Conclusions: These findings suggest that Prunus might protect the renal function and inhibit the development of renal injury by regulating factors including TGF-${\beta}1$, type IV collagen, AGEs, except AT1, so Prunus can be used for diabetic patients to prevent the progression of diabetic nephropathy.

• Journal of Acupuncture Research
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• v.22 no.5
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• pp.1-10
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• 2005

Objectives : The Present study was carried out to investigate the preventive effect of Anti-diabetic prescription 1(AD-1) on streptozotocin(STZ)-induced diabetic nephropathy. Methods : AD-1 consists of eleven herbs that have an effect on diabetes mellitus. AD-1 was given to rats with the combination of oral administration and herbal-acupuncture stimulation. The experimental animals were divided into 3 groups : normal group of rats, control group of STZ-induced diabetic rats, sample group with AD-1 treatment. Experimental diabetes was induced by the injection of STZ(60mg/kg) to e rat via the peritoneum. The effect of AD-1 on STZ-induced diabetic nephropathy was observed by measuring the serum level of creatinine and BUN. Urine secretion of albumin for 24 hours and urine level of glucose measures too. Anti-oxidative stress of AD-1 administration in living body was estimated by measuring lipid peroxide and GSH content in cortex of kidneys. Results : STZ induced increase of serum creatinine, BUN and albumin secretion were lowered by AD-1 treatment. Conclusion : The AD-1 treatment showed protective effect on rat diabetic nephropathy model, and action mechanism of the effect was thought to be concerned with anti-oxidative stress.