Hypoglycemic and Antihyperlipidemic Effect of Four Korean Medicinal Plants in Alloxan Induced Diabetic Rats

To consider potentially new hypoglycemic and antihyperlipidemic sources, aqueous extracts from four Korean medicinal plants, Chrysanthemum coronarium, Dioscorea batatas, Morus alba, Citrus unshiu, were investigated in alloxan-induced diabetic rats. To induce diabetes, 36 rats were administered alloxan orally (120 mg/kg body weight) for 2 weeks and among those 6 rats were used as a diabetic control. Effect of extracts from four medicinal plants on blood glucose levels of diabetic rats was determined at various time interval for 9 h after oral administration of the first extract at 100 mg dose /kg body weight. In addition, GOT, GPT, LDH, total cholesterol (TC) and triglyceride (TG) were determined 7 days after daily oral administration of each extract. The glucose levels of diabetic rats treated with C. coronarium and M. alba were significantly decreased, respectively, at 3 h and 5 h after administration (p<0.05). The enzyme activities of GOT, GPT and LDH of diabetic rats were also decreased in diabetic rats treated with four plant extracts respectively. In particular, the administration of extract from M. alba tends to bring the GOT, GPT and LDH values of diabetic rats to near normal. There was no significant difference in TC between diabetic control and diabetic rats treated, respectively, with extracts of C. coronarium, D. batatas and M. alba, except C.unshiu extract showing a significant decrease when compared to the diabetic control. The TC value was brought down by 33.3% fall from the value of diabetic rats, which shows more decrease than that of glibenclamide-treated ones. There was a significant difference in TG between the diabetic control and diabetic rats treated, respectively, with extracts of C. coronarium, D. batatas, M. alba and C.unshiu. The results suggest that the administration of C. coronarium and M. alba have a hypoglycemic effect in diabetic rats and their effect was equivalent to that of glibenclamide. The administration of C.unshiu shows more antihyperlipidemic effect than antidiabetic effect.