Prosopis africana Stem Bark Extract: Effects on Parasitaemia and Haematological Parameters of Plasmodium berghei -infected Mice

Abstract

Herbal medicine practitioners use Prosopis africana for the treatment of malaria in endemic regions of sub-Saharan Africa. In this study, the acclaimed antimalarial activity of aqueous extract of P. africana stem bark was investigated. Thirty mice (21.05 ± 0.56g) were randomly assigned into six groups. Group A served as uninfected control, whereas animals in groups B, C, D, E and F were infected with Plasmodium berghei (NK 65 chloroquine-sensitive), and treated for four days with 0.2ml of distilled water, 20 mg/Kg body weight (bw) of chloroquine, 100, 150, and 200 mg/Kgbw of the extract respectively. Phytochemical analysisof the extractshowed the presence of alkaloid (5.08 mg/g), anthraquinone (1.43 mg/g), flavonoids (4.72 mg/g), glycosides (4.41mg/g), phlobatannins (0.19mg/g), tannins (2.03 mg/g) and saponins (1.22 mg/g). Treatment with the aqueous extract of P. africana stem bark at 100, 150, and 200 mg/kg bw produced 89.63, 82.16 and 75.60% chemo-suppression of the parasite respectively, whereas  84.89%  was recorded in mice treated with the reference drug, chloroquine. Infection of mice with P. berghei significantly (p<0.05) reduced white blood cells, red blood cells, haemoglobin, packed cell volume and platelets counts, whereas treatment of the infected mice with the extract significantly (p<0.05) increased the level of these haematological indices.  This study showed that aqueous extract of P. africana stem bark significantly reduced the parasite in the blood of infected mice and enhance the haematological indices associated with P. berghei infection, with the best activity at 100 mg/Kg bw of the extract.