Influence of sesame oil on blood glucose, lipid peroxidation, and antioxidant status in streptozotocin diabetic rats

The present study was carried out to assess the influence of sesame oil on blood glucose, lipid peroxidation, and status of antioxidants in normal and streptozotocin (STZ) diabetic rats. Diabetes was induced in adult female albino Wistar rats weighing 180-200 g by administration of STZ (40 mg/kg of body weight) intraperitonially. Both normal and diabetic rats were fed with a commercial diet containing 2% oil supplemented with 6% sesame oil for 42 days. Diabetic rats had elevated levels of blood glucose (322.61 +/- 9.49 mg/dL), glycosylated hemoglobin, vitamin E, thiobarbituric acid-reactive substances (TBARS), and lipid hydroperoxides and decreased levels of hemoglobin, vitamin C, and reduced glutathione (GSH). An increase in glucose-6-phosphatase and fructose-1,6-bisphosphatase activities and a decrease in hexokinase activity were observed in liver and kidney tissues. When diabetic rats fed with sesame oil were compared with diabetic rats, a significant reduction in levels of blood glucose (222.02 +/- 8.27 mg/dL), glycosylated hemoglobin, TBARS, and lipid hydroperoxides and glucose-6-phosphatase and fructose-1,6-bisphosphatase activities and an elevation in hemoglobin, vitamin E, and GSH levels and hexokinase activity were observed. Thus, sesame oil consumption influences beneficially the blood glucose, glycosylated hemoglobin, lipid peroxidation, and antioxidant levels in diabetic rats.     

Antihyperglycemic effect of umbelliferone in streptozotocin-diabetic rats

The present study was designed to investigate the antihyperglycemic effect of Umbelliferone (UMB) in normal and streptozotocin (STZ)-diabetic rats. Diabetes was induced in adult male albino rats of the Wistar strain, weighing 180-200 g, by administration of STZ (40 mg/kg of body weight) intraperitoneally. Diabetic rats showed an increase in levels of blood glucose and glycosylated hemoglobin (HbA(1c)) and activities of gluconeogenic enzymes such as glucose-6-phosphatase and fructose-1,6-bisphosphatase, and a decrease in levels of plasma insulin, hemoglobin (Hb), and liver glycogen and activities of glucokinase and glucose-6-phosphate dehydrogenase. Intraperitoneal administration of UMB (10, 20, and 30 mg/kg of body weight) and glibenclamide (600 micro g/kg of body weight) in 10% dimethyl sulfoxide dissolved in water, for 45 days, produced significantly decreased levels of blood glucose and HbA(1c) and activities of glucose-6-phosphatase and fructose-1,6-bisphosphatase, while elevating levels of plasma insulin, Hb, and liver glycogen and activities of glucokinase and glucose-6-phosphate dehydrogenase to near normal levels in STZ-diabetic rats when compared with normal control rats. Normal rats treated with UMB (30 mg/kg of body weight) also showed a significant effect on glycemic control. Thus, our results show that UMB at 30 mg/kg of body weight possesses a promising antihyperglycemic effect that is comparable with glibenclamide.     

Effect of Aegle marmelos fruits on normal and streptozotocin-diabetic Wistar rats

The present study evaluates the antidiabetic effect of an aqueous extract of Aegle marmelos fruits (AMFEt) in diabetes. Female albino Wistar rats were randomly divided into five groups: normal (untreated), normal + AMFEt, streptozotocin (STZ)-treated, STZ-treated + AMFEt, and STZ-treated + glibenclamide. Rats were rendered diabetic by STZ (45 mg/kg) administered intraperitoneally. AMFEt (250 mg/kg) was given twice daily for 1 month. Blood glucose, plasma insulin, glycosylated hemoglobin, liver glycogen, and change in body weight were determined. Food intake and water intake were monitored daily. An oral glucose tolerance test was also performed to determine the effect of this extract. The results show that glucose level and glycosylated hemoglobin were increased and plasma insulin and liver glycogen were decreased in diabetic rats, and that treatment with AMFEt reversed the effects of diabetes on these biochemical parameters to near-normal levels.     

The Aqueous Extract of Withania coagulans Fruit Partially Reverses Nicotinamide/Streptozotocin-Induced Diabetes Mellitus in Rats

Abstract Withania coagulans fruit has been shown to possess antihyperglycemic properties and is used in the traditional Indian system of medicine. However, there has no systematic study of its mechanism of action. In a rat model diabetes mellitus (DM) was induced by intraperitoneal injection of nicotinamide (230?mg/kg of body weight) followed by streptozotocin at 55?mg/kg of body weight. After 96?h, mildly diabetic (MD) (fasting plasma glucose [FPG]=7-11.1?mmol/L) and severely diabetic (SD) (FPG>11.1?mmol/L) rats were treated with aqueous extract of W. coagulans fruit at doses of 125, 250, and 500?mg/kg of body weight/day orally. FPG, postprandial plasma glucose (PPPG), glycosylated hemoglobin (HbA(1c)), plasma insulin, tissue glycogen, and glucose-metabolizing enzymes were assayed at Day 30. Treatment of diabetic animals (MD and SD) with different doses of aqueous W. coagulans resulted in significantly decreased FPG, PPPG, and HbA(1c) (P<.01), whereas serum insulin increased significantly compared with that in diabetic-untreated rats (P<.01). MD and SD animals treated with aqueous W. coagulans also showed significant increases in liver and muscle glycogen compared with diabetic-untreated animals (P<.01). Moreover, activities of glucokinase and phosphofructokinase were also significantly increased (P<.01), whereas glucose-6-phosphatase activity was significantly decreased (P<.01) in MD and SD groups treated with aqueous W. coagulans compared with diabetic-untreated groups. The most effective dose of aqueous W. coagulans was 250?mg/kg of body weight. These results show that the aqueous extract of W. coagulans fruit has significant antihyperglycemic effects, which may be through the modulation of insulin levels and related enzyme activities.     

Carbohydrate Free Diet In Rats

Young rats fed for one week a diet free of carbohydrate and limited in carbohydrate precursors developed increased gluconeogenesis and decreased glucose utilization. Activities of glucose-6-phosphatase, fructose-1,6-diphosphatase, and glutamic-pyruvic transaminase in the liver were enhanced, while glucokinase activity and glucose tolerance were decreased.     

Hypoglycemic effect of Lentinus strigosus (Schwein.) Fr. crude exopolysaccharide in streptozotocin-induced diabetic rats

ABSTRACT This study reports the hypoglycemic effects of the crude exopolysaccharide (EPS) produced from submerged mycelial culture of Lentinus strigosus (Schwein.) Fr. (Family Polyporaceae) in streptozotocin (STZ)-induced diabetic rats. In a dose-dependent study, diabetic rats were treated with EPS at doses of 50-150 mg/kg of body weight for 7 days. Serum glucose and plasma insulin levels were measured in normal, STZ-induced diabetic, and EPS-treated diabetic rats. Following oral administration of EPS dosages for 7 days, the serum glucose levels in the STZ-induced diabetic rats were reduced up to 21.1% at the dose of 150 mg/kg of body weight. The results revealed that orally administered L. strigosus EPS, at the dose of 150 mg/kg, exhibited a considerable hypoglycemic effect in STZ-induced diabetic rats. Plasma insulin levels of STZ-induced diabetic rats decreased as compared to control group rats (P < .05). Although insulin levels slightly increased in the EPS-treated groups the increase was not statistically significant. The hypoglycemic potential of the EPS was further supported by histological observations of pancreatic islets of Langerhans.     

Supplementation of fenugreek leaves lower lipid profile in streptozotocin-induced diabetic rats

The present study was undertaken to evaluate the lipid-lowering effect of fenugreek leaves in diabetes mellitus. Albino Wistar rats were randomly divided into six groups: normal untreated rats; streptozotocin (STZ)-induced diabetic rats; STZ-induced rats + fenugreek leaves (0.5 g/kg of body weight); STZ-induced rats + fenugreek leaves (1 g/kg of body weight); STZ-induced rats + glibenclamide (600 microg/kg of body weight); and STZ-induced rats + insulin (6 units/kg of body weight). Rats were made diabetic by STZ (40 mg/kg) injected intraperitoneally. Fenugreek leaves were supplemented in the diet daily to diabetic rats for 45 days, and food intake was recorded daily. Blood glucose, total cholesterol, triglycerides, and free fatty acids were determined in serum, liver, heart, and kidney. Our results show that blood glucose and serum and tissue lipids were elevated in STZ-induced diabetic rats. Supplementation of fenugreek leaves lowered the lipid profile in STZ-induced diabetic rats.     

Protective effects of gamma-aminobutyric acid in rats with streptozotocin-induced diabetes

The effects of gamma-aminobutyric acid (GABA) in rats with experimental diabetes mellitus were examined. Diabetes mellitus was induced in adult male Wistar rats by streptozotocin (STZ) injection. Oral administration of GABA (100 or 200 mg/kg body weight/d) for 10 d to the diabetic rats resulted in a significant decrease in their serum glucose level. GABA also reduced the level of glycosylated protein in serum, indicating an improvement of hyperglycemic conditions. Rats with STZ-induced diabetes showed arrested body weight gain and an increase in both liver and kidney weight, whereas oral administration of GABA attenuated the organ hypertrophy induced by hyperglycemia. In addition, the degree of serum thiobarbituric acid (TBA)-reactive substance level was significantly lower in the rats treated with 100 mg GABA, and the degree of TBA-reactive substance in the liver and kidney was reduced by GABA in a dose-dependent manner. These results suggest that GABA treatment protects against the development of diabetic complications resulting from impaired glucose metabolism and enhanced oxidative stress.     

Effect of oral contraceptive steroid hormones on metabolic parameters of streptozotocin-induced diabetic rat

This study examined the effect of 0.05 mg norgestrel + 0.01 ethinyl estradiol (NEE) Kg · body wt⁻¹ on body weight, random blood glucose, glycosylated hemoglobin, and plasma insulin levels in streptozotocin-induced diabetic rats. Weight loss, blood glucose, glycosylated hemoglobin, and plasma insulin values of rats treated with NEE before and after the onset of diabetes were not significantly different from that of untreated diabetic rats. In conclusion, oral administration of these contraceptive steroid hormones does not significantly alter the metabolic parameters of diabetic rats.     

海参虫草复配物辅助降血糖作用研究

目的探讨海参虫草复配物对糖尿病大鼠糖代谢的调节作用。方法采用腹腔注射链脲佐菌素的方法建立糖尿病大鼠模型。利用海参虫草复配物(分别为300、1200mg/kg.bw)灌胃模型大鼠35d,观察其对大鼠空腹血糖、葡萄糖耐量、血清胰岛素、糖化血红蛋白、糖化血清蛋白以及肌、肝糖元等的影响。结果海参虫草复配物能显著降低糖尿病大鼠空腹血糖含量(P<0.05),提高葡萄糖耐量水平(P<0.05,P<0.01);显著降低糖化血红蛋白和糖化血清蛋白含量(P<0.05,P<0.01);显著提高糖尿病大鼠血清中胰岛素含量(P<0.05)、胰岛素分泌指数(P<0.05)和β细胞功能指数(P<0.05);增加肌、肝糖元含量(P<0.01)。结论海参虫草复配物能改善糖尿病大鼠的糖代谢水平,具有较好的辅助降糖效果。     

Beneficial effects of ginger (Zingiber officinale) on carbohydrate metabolism in streptozotocin-induced diabetic rats

Zingiber officinale (ZO), commonly known as ginger, has been traditionally used in the treatment of diabetes mellitus. Several studies have reported the hypoglycaemic properties of ginger in animal models. The present study evaluated the antihyperglycaemic effect of its aqueous extract administered orally (daily) in three different doses (100, 300, 500?mg/kg body weight) for a period of 30?d to streptozotocin (STZ)-induced diabetic rats. A dose-dependent antihyperglycaemic effect revealed a decrease of plasma glucose levels by 38 and 68?% on the 15th and 30th day, respectively, after the rats were given 500?mg/kg. The 500?mg/kg ZO significantly (P?相似文献   

Influence of Piper betle on hepatic marker enzymes and tissue antioxidant status in ethanol-treated Wistar rats

Piper betle L. is a commonly used masticatory in Asia. This study was carried out to investigate the hepatoprotective and antioxidant properties of P. betle, using ethanol intoxication as a model of hepatotoxic and oxidative damage. Ethanol-treated rats exhibited elevation of hepatic marker enzymes and disturbances in antioxidant defense when compared with normal rats. Oral administration of P. betle extract (100, 200, or 300 mg/kg body weight) for 30 days significantly (P <.05) decreased aspartate aminotransferase (AST), alanine aminotransferase (ALT), thiobarbituric acid reactive substances (TBARS), and lipid hydroperoxides in ethanol treated rats. The extract also improved the tissue antioxidant status by increasing the levels of nonenzymatic antioxidants (reduced glutathione, vitamin C, and vitamin E) and the activities of free radical-detoxifying enzymes such as superoxide dismutase, catalase, and glutathione peroxidase in liver and kidney of ethanol-treated rats. The highest dose of P. betle extract (300 mg/kg body weight) was most effective. The results were comparable with the known hepatoprotective drug, silymarin. These results indicate that P. betle could afford a significant hepatoprotective and antioxidant effect.     

The role of adrenals in diazinon-induced changes in carbohydrate metabolism in rats

Treatment of rats with diazinon (40 mg/kg, i.p.) resulted in hyperglycaemia and depletion of glycogen from the brain and peripheral tissues two hours after administration. The activities of glycogen phosphorylase and phosphoglucomutase were significantly higher in the brain and liver; that of glucose-6-phosphatase was not altered. The activities of the glycolytic enzymes hexokinase and lactate dehydrogenase were increased only in the brain. The cholinesterase activity in the brain was reduced by treatment with diazinon. The activities of the hepatic gluconeogenic enzymes fructose 1,6-diphosphatase and phosphoenolpyruvate carboxykinase were significantly increased. The lactate level was increased in the brain and blood, whereas that of pyruvate was not changed. The activity of glucose-6-phosphate dehydrogenase was not changed to any major extent. Cholesterol and ascorbic acid contents of adrenals were depleted in diazinon-treated animals. The changes were pronounced after intraperitoneal administration of 40 mg/kg diazinon, they were slight but significant after 20 mg/kg, and absent after 10 mg/kg. Hyperglycaemia and changes in carbohydrate metabolism were abolished by adrenalectomy suggesting possible involvement of adrenals.     

Absence of effects of dietary wheat bran on the activities of some key enzymes of carbohydrate and lipid metabolism in mouse liver and adipose tissue

1. The effects of a 100 g/kg dietary substitution of wheat bran on the body-weight gain, food consumption and faecal dry weight of mice given a high-sucrose diet and on the activities of some key enzymes of carbohydrate and lipid metabolism in liver and adipose tissue were studied. 2. Wheat bran had no effect on body-weight gain, food consumption or faecal dry weight. 3. Wheat bran had no effect on the activities of hepatic glucose-6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconate dehydrogenase (EC 1.1.1.44), malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) (EC 1.1.1.40), ATP-citrate (pro-3S)-lyase (EC 4.1.3.8), pyruvate kinase (EC 2.7.1.40) and fructose-1,6-bisphosphatase (EC 3.1.3.11). The activity of hepatic 6-phosphofructokinase (EC 2.7.1.11) increased but only when expressed on a body-weight basis. 4. Wheat bran had no effect on the activities of adipose tissue glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+), ATP-citrate (pro-3S)-lyase, hexokinase (EC 2.7.1.1), 6-phosphofructokinase and pyruvate kinase. 5. These results suggest that unlike guar gum and bagasse, wheat bran does not change the flux through some pathways of lipogenesis in liver and adipose tissue when mice are given high-sucrose diets.     

Protective role of Phaseolus vulgaris on changes in the fatty acid composition in experimental diabetes

The present investigation was carried out to evaluate the effect of Phaseolus vulgaris, an indigenous plant used in Unani and Ayurvedic medicine in India, on blood glucose, plasma insulin, cholesterol, triglycerides, free fatty acids, phospholipids, and fatty acid composition of total lipids in liver, kidney, and brain of normal and streptozotocin (STZ) diabetic rats. The results show that there was a significant increase in tissue cholesterol, triglycerides, free fatty acids, and phospholipids in STZ diabetic rats. The analysis of fatty acids showed that there was a significant increase in the concentrations of palmitic acid (16:1), stearic acid (18:0), and oleic acid (18:1) in liver, kidney, and brain, whereas the concentrations of linolenic acid (18:3) and arachidonic acid (20:4) were significantly decreased. Oral administration of the aqueous extract of P. vulgaris pods (200 mg/kg of body weight) for 45 days to diabetic rats decreased the concentrations of lipids and fatty acids, viz., palmitic, stearic, and oleic acids, whereas linolenic and arachidonic acids were elevated. Similarly, the administration of P. vulgaris pod extract (PPEt) to normal animals resulted in a significant hypolipidemic effect. These results suggest that PPEt exhibits hypoglycemic and hypolipidemic effects in STZ diabetic rats. It also prevents the fatty acid changes produced during diabetes. The effect of PPEt at 200 mg/kg of body weight was better than that of glibenclamide.     

牛初乳粉预防大鼠高血糖的实验研究

目的: 探讨牛初乳粉(BCP)对大鼠糖尿病的预防作用。方法: 给大鼠灌胃三个不同剂量的BCP(BCP)溶液15 d后,腹腔注射链脲霉素(STZ)55 mg/kg。注射后D7测定体重、血糖;D14除上述指标外,还测定血脂、肝肾组织SOD、GSH-Px、NOS及MDA(饮水量在注射后D 6、13 测量)。结果: 注射STZ后D7、D14 ,中剂量BCP组的血糖均显著低于STZ组(P﹤0.05, P﹤0.01)。D13 中剂量组的饮水量少于STZ组。D14 BCP各组的体重、胸腺指数与 STZ组相比差异均无显著性,5个组之间的血脂、肝MDA、肝肾SOD、GSH-Px、NOS差异均无显著性。 结论: 预防性给与中剂量BCP可缓解STZ所致的高血糖,并使STZ大鼠饮水量减少。     

Influence of Ramadan-type fasting on enzymes of carbohydrate metabolism and brush border membrane in small intestine and liver of rat used as a model

During Ramadan, Muslims the world over abstain from food and water from dawn to sunset for a month. We hypothesised that this unique model of prolonged intermittent fasting would result in specific intestinal and liver metabolic adaptations and hence alter metabolic activities. The effect of Ramadan-type fasting was studied on enzymes of carbohydrate metabolism and the brush border membrane of intestine and liver from rat used as a model. Rats were fasted (12 h) and then refed (12 h) daily for 30 d, as practised by Muslims during Ramadan. Ramadan-type fasting caused a significant decline in serum glucose, cholesterol and lactate dehydrogenase activity, whereas inorganic phosphate increased but blood urea N was not changed. Fasting resulted in increased activities of intestinal lactate (+34%), isocitrate (+63%), succinate (+83%) and malate (+106%) dehydrogenases, fructose 1,6-bisphosphatase (+17%) and glucose-6-phosphatase (+22%). Liver lactate dehydrogenase, malate dehydrogenase, glucose-6-phosphatase and fructose 1,6-bisphosphatase activities were also enhanced. However, the activities of glucose-6-phosphate dehydrogenase and malic enzyme fell significantly in the intestine but increased in liver. Although the activities of alkaline phosphatase, gamma-glutamyl transpeptidase and sucrase decreased in mucosal homogenates and brush border membrane, those of liver alkaline phosphatase, gamma-glutamyl transpeptidase and leucine aminopeptidase significantly increased. These changes were due to a respective decrease and increase of the maximal velocities of the enzyme reactions. Ramadan-type fasting caused similar effects whether the rats fasted with a daytime or night-time feeding schedule. The present results show a tremendous adaptation capacity of both liver and intestinal metabolic activities with Ramadan-type fasting in rats used as a model for Ramadan fasting in people.     

High-fructose feeding of streptozotocin-diabetic rats is associated with increased cataract formation and increased oxidative stress in the kidney

We examined the effects of high-fructose (FR) feeding on the development of diabetic complications in the lens and the kidney of streptozotocin (STZ)-diabetic rats. Male Wistar Furth rats were treated with one of two doses of STZ (HIGH STZ, 55 mg/kg body weight; MOD STZ, 35 mg/kg body weight) or vehicle alone (SHAM) and were then assigned to a control (CNTL) or 400 g FR/kg diet for 12 weeks. At the end of the study, body weight, plasma glucose and insulin concentrations differed among STZ groups (HIGH v. MOD v. SHAM, P < 0.001) but did not differ due to diet. Plasma FR concentrations were significantly higher in FR-fed v. CNTL-fed groups (P < 0.0001) and in HIGH-STZ groups v. MOD-STZ and SHAM groups (P < 0.0004 and P < 0.0001 respectively). Focal length variability of the lens, a quantitative measure of cataract formation, was increased in the HIGH STZ, FR group compared with the HIGH STZ, CNTL group (P < 0.01). The concentration of H2O2 in kidney microsomes was significantly higher in HIGH STZ, FR rats v. HIGH STZ, CNTL rats (P < 0.01). Micro-albuminuria was not observed in any of the groups examined, and there was no evidence of extensive histological damage in the kidney from any rats. Under conditions of severe hyperglycaemia, high FR intake promotes the development of cataracts in the lens of the eye, and results in increased concentrations of substances indicative of oxidative stress in the kidney. Although FR has been suggested as a carbohydrate source for diabetics, a high FR diet coupled with hyperglycaemia produces effects that may promote some of the complications associated with diabetes.     

Metabolic alterations in liver and kidney following chronic methyl mercury treatment and withdrawal

Daily intraperitoneal injection of methyl mercury (0.4 and 4 mg/kg) for 45 days to rats decreased liver size without producing any significant change in adrenal, cardiac, renal, testicular, and body weight. Chronic exposure to either dose of this organomercurial augmented the activities of renal and hepatic pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose 1,6-diphosphatase and glucose 6-phosphatase, elevated the concentration of blood glucose and urea, as well as reduced liver glycogen content. As expected, the degree of alterations in various parameters studied was greater in animals which were injected with the higher dose (4 mg/kg) of methyl mercury. Furthermore, withdrawal of treatment for 28 days in rats that had previously been given the 4 mg/kg daily dose of methyl mercury for 45 days, generally failed to reverse the observed metabolic changes in hepatic and renal carbohydrate metabolism. Our results suggest that the gluconeogenic potential of both liver and kidney is markedly enhanced in animals chronically treated with methyl mercury and that the metabolic alterations persist even after a 28 day period of abstinence from heavy metal treatment.     

Effects of malted barley extract and banaba extract on blood glucose levels in genetically diabetic mice

This study investigated the therapeutic effects of a malted barley extract (MBE) and of banaba extract on blood glucose, insulin, and other biochemical parameters in genetically diabetic mice (C57BL/KsJ(-) m (+/+) Lepr (db)). The mice were divided into three groups-control, MBE, and banaba-according to supplementation. Both MBE and banaba extracts were orally administered to the animals for 12 weeks at doses of 62.5 mg/kg of body weight and 0.8 mg/kg of body weight, respectively. The body and organ (liver and kidney) weights were not different among groups. Fasting blood glucose was significantly lower in the MBE group compared with the control (P < .05). Hemoglobin A1c content was significantly lower in the MBE group compared with either the control or banaba group (P < .05). There was no significant difference in the serum insulin level among groups. The glucose-6-phosphatase activity in kidney was significantly lower in both the MBE and banaba groups compared with the control group (P < .05), but there was no significant difference between the MBE and banaba groups. Therefore, the results of this study demonstrate that MBE alleviates many of the symptoms of diabetes in genetically obese mice and may offer promise as a therapeutic supplement for the normalization of blood glucose levels in humans with hyperglycemia and have beneficial effects in patients with non-insulin-dependent diabetes mellitus.