Effect of inulin supplementation in male mice fed with high fat diet on biochemical profile and α-amylase gene expression

Purpose: To evaluate the preventive and therapeutic effects of inulin supplementation in Naval Medical Research Institute (NMRI) male mice fed with high fat diet. Methods: NMRI male mice (n = 36) were divided into three groups. Control (C1), obese (O1) and experimental mice (E1) were fed during 8 weeks as follows: C1 with normal rodent pellet, O1 with high fat diet, and E1 with high fat diet plus 20 % inulin. C2, O2, and E2 were fed as follows: C2 with normal rodent pellets for 12 weeks; O2 with high fat diet during 8 weeks and switched to normal rodent pellet during next 4 weeks; and E2 with high fat diet over a period of 8 weeks and switched to normal rodent pellet plus 20 % inulin for 4 weeks. Body weight, serum glucose, triglycerides, total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), and hepatic α-amylase gene expression were measured. Results: Groups receiving high fat diet showed higher weight (30.71 ± 0.66 g in O2, p < 0.001), nonfasting blood glucose levels (257.69 ± 5.10 mg/dl in O2, p < 0.001), TG (282.15 ± 1.83 mg/dl in O2, (p < 0.001)), and cholesterol levels (335.72 ± 2.23 mg/dl in O2, (p < 0.001)), compared with control. In C2 group, mean body weight was 25.71 ± 0.54 g, non-fasting blood level 161.54 ± 4.48 mg/dl, TG level 214.29 ± 5.54 mg/dl, and cholesterol level 164.29 ±4.57 mg/dl. Compared to obese group, mice receiving inulin showed lower blood glucose levels (223.10 ± 8.7 mg/dl in E2, p < 0.001), body weight (27.86 ± 0.57 g in E2, p < 0.001), TG (232.14 ± 4.02 mg/dl in E2, p < 0.001) and cholesterol (249.97 ± 2.28 in E2, p < 0.001). A slight decrease in hepatic α-amylase gene expression was observed only in E1. Conclusion: Besides its sweetening properties, inulin may also find use as a potential anti-obesity compound.

Effect of Astragalus membranaceus (Fisch) Bunge extract on streptozocin-induced diabetic in rats

Purpose: To investigate the effect of Astragalus membranaceus (Fisch.) Bunge. extract (AMBE) on streptozotocin-induced diabetic rats. Methods: The aqueous extract of AMB was obtained by steeping the dried Astragalus membranaceus (Fisch.) Bunge. in water at 60 oC three times, each for 1 h, before first drying in an oven at 100 oC and then freeze-drying the last extract thus obtained. Diabete model rats was induced by a single intraperitoneal injection of a freshly prepared solution of streptozotocin (50 mg/kg). The rats were randomly divided into 6 groups of ten rats each: negative control group, normal control group, reference group (glibenclamide1 mg/kgbody weight) as well as AMB extract groups, namely, 40, 80 and 160 mg/kg body weight. Antihyperglycemic effect was measured by blood glucose and plasma insulin levels. Oxidative stress was evaluated in liver and kidney by antioxidant markers, viz, lipidperoxidation (LPO), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT), while blood serum levels of creatinine and urea were also determined in both diabetic control and treated rats. Results: Compared with diabetic rats, oral administration of AMBE at a concentration of 160 mg/kg daily for 30 days showed a significant decrease in fasting blood glucose (109.438 ± 3.52, p < 0.05) and increased insulin level (13.96 ± 0.74, p < 0.05). Furthermore, it significantly reduced biochemical parameters (serum creatinine, 0.86 ± 0.29, p < 0.05) and serum urea (45.14 ± 1.79, p < 0.05). The treatment also resulted in significant increase in GSH (49.21 ± 2.59, p < 0.05), GPx (11.96 ± 1.16, p < 0.05), SOD (14.13 ± 0.49, p < 0.05), CAT (83.25 ± 3.14, p < 0.05) level in the liver and kidney of diabetic rats. Conclusion: The results suggest that AMBE may effectively normalize impaired antioxidant status in streptozotocin-induced diabetes in a dose-dependent manner. AMBE has a protective effect against lipid peroxidation by scavenging free radicals and is thus capable of reducing the risk of diabetic complications.