Antihyperglycaemic and antihyperlipidemic effects of ethanolic extract of syzygium aromaticum(clove)/in streptozotocin induced diabetic rats

Objective: The purpose of the present study was to assess the effect of ethanolic extract of Syzygium aromaticum buds in streptozotocin(STZ) induced diabetes in rats. Study Design: Randomized controlled trial Place and Duration of Study: This study was conducted at the Department of Pharmacology, Islamic International Medical College, Rawalpindi from 1 ^st Jan 2011 to 30 ^st June 2011. Materials and Methods: Single injection of STZ was given intraperitoneally to rats and rats showed fasting glucose level over 280mg/dl were included in the study. After induction of diabetes all rats were divided into, normal control group (A), diabetes positive control group (B), and the two groups (C and D) served as experimental groups while group E served as standard as it received glibenclamide. Group C and D diabetic experimental rats received ethanolic extract of Syzygium aromaticum at 250 mg/kg and 500mg/kg of body weight orally for eight weeks on daily basis. On the other hand group E rats received glibenclamide at 0.5 mg/kg body weight orally for eight weeks. Blood samples were collected after eight weeks. Results: The diabetic positive group rats showed variable increase in serum levels of glucose, triglycerides, low density lipoprotein (LDL) and total cholesterol levels. Serum high density lipoprotein (HDL) levels decreased in diabetic positive group. Syzygium aromaticum 250mg/kg and 500mg/kg dose and glibenclamide significantly decreased the levels of these parameters in rats. On comparison Syzygium aromaticum 500mg/kg dose reduced glucose and lipid levels more, effectively than the 250mg/kg dose of Syzygium aromaticum and glibenclamide. Syzygium aromaticum constituents, especially polyphenols and flavonoids have strong anti-oxidant activity which might be involved in glucose and lipid lowering effect. Conclusion: Syzygium aromaticum ethanolic extract decrease glucose and lipid levels in experimentally induced diabetic rats.