Antiplasmodial Activity and Toxicological Profile of Alkaloids Obtained from Securideca longipedunculata

Abstract

Malaria is a public health problem that has reduced societal productivity particularly arising from resistance to common orthodox drugs. We hypothesized that the available diverse plant resources in Nigeria can be used to resolve the problem of resistance. Securideca longipedunculata is a medicinal herb, used locally in the treatment of malaria. Fifteen albino mice were grouped in five and administered 100, 200 and 400 mg/kg bw, while the last two groups represent the negative and positive controls. Twenty four Wistar rat were grouped into two for toxicological analysis. The test group was administered 200 mg/kg bw of the extract on alternate days while the control group was given normal saline for 4 weeks. Blood parameters were monitored on a weekly basis, with the liver, kidney, heart and spleen harvested for histopathology. The extract had both in vitro and in vivo antiplasmodial activity of IC50 of 4.65 µg/ml and 1216 parasite/µl. In the toxicity studies, RBC count and PCV continuously decreased compared to the control, while urea and bilirubin concentrations were significantly (p˂0.05) higher than the control, indicative of damage to the RBC, kidney and liver. Similarly, serum ALT and AST activities were significantly (p˂0.05) higher compared to the control, also indicative of liver damage and hemolysis. However, there was no significant (p˂0.05) change in the white blood cell indices. Histopathological analysis revealed leucocyte infiltration, vascular congestion and inflammation in the kidney and liver. Thus, the extract had adverse effect on RBC count, kidney and liver, although could serve as a potential target for malaria if bioassay guided fractionation is further carried out to differentiate between the toxic and the antiplasmodial agents.