Evaluation of Aqueous Extract of Stonebreaker (Phyllantus amarus) Leaves on Biochemical Indices in Scopolamine-induced Amnesic Albino Rat

Abstract

Phyllanthus amarus (PA) are widely distributed in most tropical and subtropical countries to treat chronic liver disease. However, in folklore, the aqueous extract of Phyllantus amarus had been employed for treatment of epilepsy and nervous debility. This study seeks to evaluate the toxicology and the effect of aqueous extracts of stonebreaker (Phyllantus amarus) leaves on biochemical indices in scopolamine-induced amnesic albino rats. All in vitro antioxidant assays shows Phyllantus amarus possess high antioxidant activities. Furthermore, acute toxicity test was carried out on the sample to determine a safe dosage. Twenty-five rats were acclimatized and randomly allocated into 5 groups containing 5 rats per group, (5, 50, 500, 2000 mg/kg) of the samples were administered once to the rats and observed for 14 days. Biochemical assays such as AST, ALT, ALP were carried out on blood sample after sacrificing. Safe doses of 50 and 500 mg/kg were determined for further experiment. Thirty-five male wistar rats were acclimatized and randomly divided into 7 groups of 5 rats per group. The rats were treated with 50 and 500 mg/kg aqueous extracts and donepezil for 14 days. After 14 days, scopolamine was induced and Y-Maze and Water maze cognitive behavioral studies were carried out on the rats to evaluate the amnesic effect. The rats were sacrificed and homogenized for other biochemical assays which include acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and monoamine oxidase (MAO). The results of the study revealed that PA (50 and 500 mg/kg) could ameliorate amnesia in both the behavioral models, and the investigated doses of PA also showed a significant decrease (p<0.05) in AChE, BChE and MAO,in comparison to scopolamine induced group only. These results were also comparable to those of donepezil, the reference drug used in this study. Phyllantus amarus could constitute a lead to discovery of a novel drug for the treatment of amnesia. Oral administration of Phyllantus amarus is safe and has no adverse effect on rat liver and kidney.