Abstract

The antioxidant activity of aqueous extract of leaves of Ageratum conyzoides (AC) in the serum of male diabetic rats was evaluated using Ferric Reducing Antioxidant Power (FRAP) assays, by determination of malonadehydes, lipid hydroperoxydes and protein thiol groups. The plant extract was tested at doses of 100, 200 and 300 mg/kg on diabetic rats during three weeks of treatment; glibenclamide (10 mg/kg) was used as positive control. Glycaemia of diabetic rats was also determined, at the beginning and at the end of the experimentation. The results showed that A. conyzoides did not have an incidence in serum protein thiols and serum malonaldehydes level. Nevertheless, the aqueous extract induced lowering of lipid hydroperoxides in the groups treated with 100 mg/kg (p ≤ 0.01) and 200 mg/kg (p ≤ 0.01) when compared to the negative control group. Power (FRAP) was also higher in the 100 mg/kg group. In addition, glycaemia was decreased at the ferric reducing antioxidant the third week in the group receiving 200 mg/kg (p ≤ 0.01) and 300 mg/kg (p ≤ 0.01). A. conyzoides had a positive effect on the oxidation-reduction system on streptozotocin induced diabetic rats and improved glycaemia of diabetic rats.

Keys words: Ageratum conyzoides, antioxidant, antihyperglycemic, streptozotocin, diabetic rats.