Use of Nigerian Medicinal Plants Protected Liver from Injury in Plasmodium berghei Infected Mice.

The effects of ethanol leaf extracts of Spilanthes uliginosa, Ocimum basilicum, Hyptis spicigera and Cymbopogon citratus on mice infected with malaria parasite was investigated. Eighty four (84) swiss mice of both sexes were used for the study. All the mice were passaged intraperitoneally with 0.2 ml parasitized blood suspension and parasitemia assessed by Geimsa stain thin blood films after seventy two hours. The mice were divided into 6 groups namely; A, B, C, D, E and F. Groups B, C, D and E were subdivided into three (3): B1, B2, B3, C1, C2, C3, D1, D2, D3, E1, E2 and E3. Both groups and subgroups contained 6 mice each. The subgroups were treated with the extracts of Spilanthes uliginosa (Sw), Ocimum basilicum, Hyptis spiligera and Cymbopogon citratus each for five (5) consecutive days with 200, 400 and 800 mg/kg body weight via oral intubation daily respectively. The results indicated a general significant (P<0.05) decrease in the average body weight of the parasitized untreated mice while the histological photomicrographs showed alterations in the liver architecture of parasitized untreated mice and restorative effects of all the plant extracts and standard drug on the liver architecture of the parasitized treated mice.

Antiplasmodial Activity of Ethanolic Leaf Extracts of Spilanthes uliginosa, Ocimum basilicum (Sweet Basil), Hyptis spicigera and Cymbopogon citratus on Mice Exposed to Plasmodium berghei Nk 65.

In Africa and elsewhere, medicinal plants including Spilanthes uliginosa, Ocimum basilicum, Hyptis spicigera and Cymbopogon citratus are still widely used in the treatment of malaria and other ailments. The aim of the present study was to investigate in vivo antiplasmodial effect of ethanolic leaf extract of these plants in mice. Oral acute toxicity of the extracts was evaluated in mice using modified Lorke’s method and their in vivo anti-plasmodial effect against early infection, curative effect against established infection and prophylactic effect against residual infection were studied using total WBC count in chloroquine-sensitive Plasmodium berghei NK 65-infected mice. The oral median lethal dose of the extract in mice was determined to be greater than 2000 mg kg-1 body weight. The results indicated a significant (P<0.05) daily increase in the level of parasitaemia in the parasitized untreated groups and a significant (P<0.05) dose dependent decrease in the level of parasitaemia in the parasitized groups treated with varying doses of the various medicinal plants and the standard drug. Overall, the dose dependent effects were in the order of: 5mg/kg body weight of chloroquine > 800 mg/kg > 400 mg/kg > 200 mg/kg body weight of the plant extracts with the efficacy of the plants in the order of: H. Spicigera > O. basilicum > C. citratus > S. uliginosa (Sw) with minor variations. The implications of these results is that Spilanthes uliginosa, Ocimum basilicum, Hyptis spicigera and Cymbopogon citratus ethanolic leaf extracts posses potent antimalarial effects and may therefore serve as potential sources of safe, effective and affordable antimalarial drugs.