Antidiabetic Activity of Hydroalcoholic Extract of Myrtus communis (Myrtle) Fruits in Streptozotocin‑Induced and Dexamethasone‑Induced Diabetic Rats

Background: Diabetes mellitus is characterized by an increase in blood glucose levels, resulting in insufficiency of insulin secretion, insulin resistance, or both. Objective: The effects of hydroalcoholic extract of the Myrtus communis (myrtle) fruits on Wistar rats were investigated in two types of diabetes mellitus. Materials and Methods: Intraperitoneal administration of streptozotocin (60 mg/kg) was used to induce Type I diabetes. Type II diabetes was induced by subcutaneous injection of 1 mg/kg/day dexamethasone for 10 days. Two groups of the diabetic animals received the hydroalcoholic extract of the fruit by gavage (250 mg/kg and 500 mg/kg for 45 and 10 days) and the diabetic control groups receiving distilled water. Results: The hydroalcoholic extract of M. communis fruits reduced the serum levels of the glucose, triglyceride, urine volume, urine protein, and malondialdehyde at the end of the 45 day. In Type II diabetic rats, there was a significant effect on plasma glucose levels. On this day, blood glucose‑lowering effect was significantly observed after insulin administration as C2>D2M500>D2M250>D2 (P ≤ 0.05). The plasma level of insulin was completely reversed. There were no differences in the other biochemical parameters. Conclusion: The hydroalcoholic extract of M. communis fruits has a significant effect on the improvement of diabetes mellitus complications especially Type II diabetic animals, which begins with insulin resistance.