Antiplasmodial and analgesic activities of Clausena anisata

Antiplasmodial and analgesic activities of the leaf extract and fractions of Clausena anisata (C. anisata) were evaluated for antimalarial and analgesic activities.

The crude leaf extract (39-117 mg/kg) and fractions (chloroform and acqeous; 78 mg/kg) of C. anisata were investigated for antiplasmodial activity against chloroquine-sensitive Plasmodium berghei (P. berghei) infections in mice using suppressive, prophylactic and curative models and analgesic activity against acetic acid, formalin and heat-induced pains. Artesunate, 5 mg/kg and pyrimethamine, 1.2 mg/kg were used as positive controls. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice.

The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine-sensitive P. berghei in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (P<0.001). They also improved the mean survival time (MST) from 17 to 21 days relative to control (P<0.01 - 0.001). On chemically and thermally-induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (P<0.001) and in a dose-dependent fashion.

The antiplasmodial and analgesic effects of this plant may in part be mediated through its chemical constituents and it can be concluded that the C. anisata possess significant antimalarial and analgesic properties.