Antidiabetic Potentials of Essential Oil Extracted from the Leaves of Hoslundia opposita Vahl.

This study was aimed at assessing the potential of essential oil from the leaf of Hoslundia opposita in the treatment of diabetes. Forty-eight rats (Rattus norvegicus) were randomized into two groups; nondiabetic and diabetic groups, each with four subgroups. Animals in the diabetic group were induced with diabetes using a single dose of alloxan monohydrate, 160 mg/kg body weight (b. wt.). The rats were treated with 110 and 220 mg/kg b. wt. of the essential oil. All treatments were administered, intraperitoneally, once a day for 4 days. In the nondiabetic condition, there was no effect of the oil on fasting blood glucose (FBG) levels in rats. In diabetic rats, the oil caused a significant reduction in FBG levels. Treatment with 110 mg/kg b. wt. of the oil reduced FBG almost to the normoglycemic level by day 4 and the overall glucose excursion during a 3-h intraperitoneal glucose tolerance test approached the baseline level at 120 min. Also, hepatic glycogen was significantly higher, while the glucose concentrations were lower in the diabetic-treated group when compared with the diabetic untreated group. Histological examinations revealed a mildly distorted architecture of the pancreatic islets beta-cells of diabetic rats treated with the oil, while those of the untreated rats were severely degenerated. Overall, the in vivo antihyperglycemic activity of the essential oil may prove to be of clinical importance in the management of type 2 diabetes.