Protective effects and mechanism of icariin against vascular function in diabetic mice / 中国药科大学学报

@#To explore the effects and molecular mechanism of icariin on the vascular function of mice with type 1 diabetes induced by alloxan, type 1 diabetic mice model was established by intraperitoneal injection with 200 mg/kg alloxan.After oral administration with icariin (60, 120 mg/kg) daily for 2 weeks, blood glucose, body weight, food intake and water intake were detected.To evaluate the impact of icariin on the function of isolated vascular ring contraction and relaxation, thoracic aortas of mice were removed and the Ach-induced vascular ring relaxation, Phe-induced vascular ring contraction, SNP-induced vascular ring relaxation and KCl-induced vascular ring contraction response were detected.To further confirm the mechanism of icariin to improve vascular function, human umbilical vein endothelial cells (HUVECs) were induced by high glucose (HG) in vitro.Western blot was used to detect the effect of icariin on eNOS, p-eNOS, p38 MAPK and p-p38 MAPK expressions in HG-induced human umbilical vein endothelial cells (HUVECs).The results indicated that icariin significantly ameliorated the weight loss and dampened the increase in water intake of the diabetic mice.Meanwhile, icariin had a certain ameliorative effect on blood glucose and food intake without significant difference.The results of isolated thoracic aortas vascular rings contraction and vasodilation function indicated that icariin significantly improved Phe-induced vascular contraction and Ach‐induced vascular relaxation.Meanwhile, icariin had a certain ameliorative effect on KCl-induced vascular contraction response without significant difference.However, no significant change was observed on endothelium‐independent vascular rings relaxation response induced by SNP after treatment with icariin.Results of Western blot showed that icariin inhibited the expression of p-p38 MAPK and induced expression of p-eNOS in the high glucose-induced HUVECs cell model.Therefore, icariin may attenuate alloxan-induced type 1 diabetic mice vascular diastolic function by inhibiting expression of p-p38 MAPK and inducing expression of p-eNOS.

Hypoglycemic effect of alismoxide in type 2 diabetic mice / 中国药理学通报

Aim To investigate the hypoglycemic effect of alismoxide. Methods Type 2 diabetes mellitus (DM) mouse model induced by combined administration of streptozotocin and nicotinamide was adopted. Three weeks later, blood glucose of blank control group and type 2 diabetic mouse model group was measured on day 21 , and oral glucose tolerance test(OGTT) was carried out on day 2 2 , respectively. After type 2 diabetic mouse model was successfully established, rosiglitazorie was chosen as positive drug. Oral administration of rosiglitazone at dose of 10 mgk g-1 daily was performed for three weeks in positive group. Oral administration of alismoxide at dose of 5 , 10 and 20 mg kg"1 daily for three weeks was carried out in alismoxide different dose group, respectively. Furthermore, influence of alismoxide on differentiation was investigated in 3T3-L1 pre-adipocytes, and Oil red 0 staining was adopted. Results Not only blood glucose was decreased by alismoxide in type 2 DM mice, but also hypoglycemic trend was exhibited during OGTT. Furthermore, at concentration of 0. 5 and 1 fimol L " 1 , alismoxide promoted 3T3-L1 pre-adipocyte differentiation. Conclusions It suggests that alismoxide might possess hypoglycemic property and accelerate pre-adipocyte differentiation; however, the mechanism involved needs further study.

Effects of Saponin Extracted from Zea Mays L (ZMLS) on Pathogenic Diabetic Mouse Model Caused by Administration of Alloxan and Glucose / 中华中医药杂志

Objective: To observe the effects of Saponin Extracted from Zea Mays L(ZMLS) on reducing blood sugar in pathogenic diabetic mouse models.Methods: The pathogenic diabetic mouse models were established successfully by intravenous injection of small dose of alloxan and intragastric administration of glucose.Modeling state of pathogenic diabetic mice and the effects of Saponin Extracted from Zea Mays L(ZMLS) on pathogenic diabetic mouse models were observed through the levels of blood sugar and serum of insulin and the pathology changes of islet cells.Results: It was successful to establish pathogenic diabetic mouse models by intravenous injection of small dose of alloxan and intragastric administration of glucose.ZMLS had good action of lowering the level of blood glucose on this model and had good action of preventing the pancreatic island ?-cell from the injury induced by drugs.Conclusion: ZMLS has good therapy effects on pathogenic diabetic mouse models induced by intravenous injection of small dose of alloxan and intragastric administration of glucose.

Supplementary Effect of the High Dietary Fiber Rice on Blood Glucose in Diabetic KK Mice

This study was carried out to investigate the supplementary effects of Suwon 464, which has over two times of dietary fiber content compared with normal rice (Ilpum), on blood glucose in diabetic mice. We supplied 5 kinds of experimental diets (corn starch diet as a control (CO), Ilpum polished rice diet (IP), Ilpum brown rice diet (IB), polished rice diet (SP) and brown rice diet (SB) of Suwon 464) to diabetic mice for 8 weeks, after analyzing dietary fiber contents of 5 experimental diets. Diet intake, body weight and contents of blood glucose, hemoglobin A(1c) and insulin were measured. The dietary fiber contents in CO, IP, IB, SP, and SB diets were 1.0, 1.2, 1.4, 1.4, and 2.0% respectively. Body weight was lower in SB group than the other groups though there was no significant difference in diet intake among experimental groups. The concentration of blood glucose in diabetic mice was lower in SB group than the other groups during the supplementary period of experimental diets. The hemoglobin A(1c) and serum insulin levels were lower in SP and SB groups. These results suggested that the brown rice of Suwon 464 with high dietary fiber can control diabetes in diabetic mice by reducing the blood glucose and hemoglobin A(1c).

Supplementary Effect of the High Dietary Fiber Rice on Lipid Metabolism in Diabetic KK Mice

This study was conducted to investigate the supplementary effects of Suwon 464 developed by Rural Development Administration, which has over two times of dietary fiber content compared with normal rice (Ilpum), on lipid metabolism in diabetic mice. We supplied 5 kinds of experimental diets (corn starch diet as a control (CO), Ilpum polished rice diet (IP), Ilpum brown rice diet (IB), polished rice diet (SP) and brown rice diet (SB) of Suwon 464) to diabetic mice for 8 weeks, after analyzing dietary fiber contents of 5 experimental diets. Diet intake, body weight, organ weights, and lipids levels of serum, liver and feces were measured. The dietary fiber contents in CO, IP, IB, SP, and SB diets were 1.0, 1.2, 1.4, 1.4, and 2.0% respectively. Body weight and liver and epididymal fat pad weights were lower in SB group than the other groups though there was no significant difference in diet intake among experimental groups. The concentrations of serum triglyceride was lower in SP and SB groups than CO and IP groups. The levels of hepatic total lipid and total cholesterol were significantly lower in SP and SB groups than CO group, and the level of hepatic triglyceride was lower in IB, SP and SB groups than CO group. The levels of total lipid and triglyceride excreted in feces were higher in IB, SP and SB, and the level of total cholesterol in feces was higher in SP and SB groups than CO group. These results suggested that the high dietary fiber rice (Suwon 464) decrease the triglyceride or total cholesterol concentrations of serum and liver by increasing of fecal lipid excretion in diabetic mice.

Supplementary Effect of gamma-Oryzanol on Lipid Metabolism in Diabetic KK Mice

This study was carried out to investigate the supplementary effects of gamma-oryzanol extracted from rice bran on lipid metabolism in diabetic mice. We supplied 2 kinds of experimental diets (CO without and GO with 0.2% gamma-oryzanol) to diabetic mice for 8 weeks. Diet intake, body weight, organ weight, contents of serum and hepatic lipid profiles, and fecal lipid levels were measured. Though there was no significant difference in diet intake, body weight change and organ weight between experimental groups, the concentration of serum total cholesterol and hepatic total lipid, total cholesterol and HMG-CoA reductase activity was significantly lower in GO group treated with 0.2% gamma-oryzanol of diet than CO group after supplementary period of experimental diets. And total lipid, triglyceride, total cholesterol, and bile acid levels excreted to feces were significantly higher in GO group than CO group. These results suggest that gamma-oryzanol decrease the serum and hepatic lipid levels by lowing HMG-CoA reductase activity or increasing the contents of fecal lipid in diabetic KK mice.