ANTIPLASMODIAL POTENTIAL AND SUBCHRONIC TOXICITY OF CYSTEINE PROTEASE INHIBITORS FROM CALOTROPIS PROCERA

Abstract

Cysteine protease of plasmodium parasite play major roles in the survival of this organism inside its host. Various extraction media which include Sodium Chloride, Sodium Hydroxide, Hydrochloric acid,Sodium phosphate buffer and distilled Water were used to evaluate Leave,root,flowers,latex and stem bark of Calotropis procera for Cysteine Protease inhibitory activity against Papain enzyme.Among the extraction media Sodium phosphate buffer extract of latex of Calotropis procera with higher Protease inhibitory activity was concentrated by cold acetone precipitation and freeze dried as crude extract.The effect of this extract on subchronic toxicity studies in mice was carried out. Inhibition of Plasmodium berghei Cysteine Protease and invivo Plasmodium berghei infected mice by this extract in graded doses of 20,30 and 50mg/kg body weight were evaluated.The crude extract showed inhibitory activity against Cysteine protease of Plasmodium berghei with IC50 value of 25.50 µg/ml . In invivo model, the highest level of parasitemia suppression of 48% was observed in 50 mg/kg body weight of the crude inhibitor extract.Subchronic toxicity of the extract at 50mg/kg body weight concentration revealed statistical significant elevation in body weight and Alanine transaminase enzyme.Total protein and glucose concentration were found to be elevated as doses increases, but no significant changes were observed in PCV,triacylglycerol,Aspartate transaminase and Alkaline Phosphotase.This result showed that crude cysteine protease inhibitor from Latex of Calotropis procera is active against plasmodium Cysteine Protease and in a rodent malaria model.It also sugest further investigation of the anti-malarial activities from Latex of this plant.