Effect of hydroalcohol extract of lemon (Citrus limon) peel on a rat model of type 2 diabetes
Purpose: To determine the effect of the hydroalcohol extract of lemon peel (LP) on a rat model of type 2 diabetes (T2D).
Method: The rat model of T2D by injection of streptozotocin was established. The effects of a hydroalcoholic extract of LP was characterised on a rat model of type 2 diabetes based on body weight, food intake, fasting blood glucose (FBG), glucose tolerance test, and insulin tolerance test. Antioxidant activity and oxidative stress were analysed by superoxide dismutase (SOD) and malonaldehyde (MDA) assays.
Results: In acute toxicity studies, administration of LP extract at 2000 mg/kg orally did not cause any symptoms of poisoning or death after 14 days. The body weight of rats increased after treatment with LP extracts. Food intake in diabetic rats decreased with LP extract treatment. Continual treatment with LP extracts for 35 days significantly reduced blood glucose levels in diabetic rats. Glucose tolerance improved, and insulin resistance was reduced after treatment with LP extracts. SOD and MDA data indicate that treatment with LP extract alleviated the oxidative stress in diabetic rats as well as enhanced the antioxidant activity of liver in a dosage-dependent manner.
Conclusion: LP extract decreased food intake and FBG, but increased body weight in rats. The effect of LP on T2D is likely related to improved antioxidant activity and reduced oxidative stress. Thus, LP extract has potentials for the treatment of T2D.
Keywords: Lemon peel, Type 2 diabetes, Antioxidant activity, Glucose tolerance, Insulin tolerance