Antitrypanosomal activity of Argemone mexicana extract and fractions in the animal model of Trypanosoma brucei brucei infection

Abstract

Abstract Background This study investigated the antitrypanosomal activity of Argemone mexicana extract and fractions in the animal model of Trypanosoma brucei brucei infection. Methods The whole plant was cold-macerated with methanol. The liquid–liquid partitioning of the extract with n-hexane, ethyl acetate, butanol, and water produced various fractions of the extract. Infection was established by the inoculation of T. brucei brucei-infected red blood cells in the animals. Treatment with the extract and fractions was done orally for 5 days postinfection at 200 and 400 mg/kg doses. Diminazene aceturate 3.5 mg/kg and 5 mL/kg 10% Tween 80 served as standard and vehicle control, respectively. Parasite load, packed cell volume (PCV), animal body weight, and survival as well as serum liver function enzymes’ activities were also assessed. Results The extract and the n-hexane fraction showed the presence of all the tested phytocompounds except tannins and cardiac glycosides, respectively. The extract showed a reduction in parasitemia while the order of activity for the fractions was n-hexane ≫ water ≫ butanol ≫ ethyl acetate. The n-hexane fraction produced complete protection against parasite-induced mortality just like the reference standard and a higher increase in PCV compared with the reference standard. The extract, n-hexane, and water fractions showed protection against infection-induced liver damage with a significant (P < 0.05) difference when compared to the vehicle control group. Conclusion A. mexicana showed antitrypanosomal activity which may be attributed to the presence of phytocompounds particularly saponins, which were present in the extract and fractions that showed antitrypanosomal activity but absent in fractions that showed no or weak antitrypanosomal activity.