Improvement of Diabetic Complication by Hydrangea Dulcis Folium in Streptozotocin-Induced Diabetic Rats

Abstract

The improvement of diabetic complications such as lipid lowering and anti-oxidative potential of Hydrangea Dulcis Folium (HDF) was studied in streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were divided into 3 groups after induction of streptozotocin (STZ)-diabetes: normal control; diabetic control; diabetic-HDF supplement (hot water extract 40 g/kg diet); and fed experimental diets for 3 weeks. Serum glucose and insulin concentrations, serum lipid profile, intraperitoneal glucose tolerance test, and liver cytosolic antioxidant enzyme levels were measured. The HDF supplement significantly decreased serum glucose concentration, increased insulin level, and improved glucose homeostasis in diabetic control rats. The total cholesterol and triglyceride concentrations in the serum and liver were markedly reduced by HDF treatment in STZ-diabetic rats. Moreover, low density lipoprotein (LDL)-, VLDL-, and high density lipoprotein (HDL)-cholesterol levels were ameliorated in HDF supplemented diabetic rats. Decreased fecal excretions of cholesterol, triglyceride, and bile acid in diabetic rats were significantly increased by HDF consumption. HDF supplement reversed the effects of the oxidative stress system of liver in diabetic rats. Lipid peroxidation of diabetic rats, assessed by thiobarbituric acid reactive substance (TBARS), as well as superoxide dismutase (SOD) activities were significantly increased, and glutathione contents were decreased in diabetic rats. HDF supplement reverted these parameters to near normal value. Our data suggest that HDF supplement could be used to improve the glucose and lipid metabolism as well as to reduce the imbalance between the generation of reactive oxygen species (ROS) and the scavenging enzyme activity in preventing diabetic complications.