Toxicological Effects, Prophylactic and Curative Activity of Rauwolfia vomitoria Leaf Extracts on Plasmodium Berghei NK 65 infected Swiss albino mice| Biomed Grid

This study evaluates prophylactic and curative antiplasmodial effects of Rauwolfia vomitoria leaf extracts on Plasmodium berghei NK 65. The extracts of the leaves at 100, 200 and 400 mg kg-1 body weight/day dose levels were used to treat the test groups 72 hours before infection for the prophylactic test and 72 hours post infection for the curative test while a standard antimalarial drug, chloroquine, at a dose of 5 mg kg-1 body weight was administered on the positive control group. The negative control groups were left untreated. The level of parasitemia, Percentage Packed Cell Volume (% PCV), erythrocytes (RBC) and leukocytes (WBC) counts in the different groups were monitored also, bicarbonate, creatinine, uric acid, urea, calcium level and histological effects of extracts were determined during the period of study. Qualitative and quantitative phytochemicals of water and ethanol leaf extracts were determined. The water and ethanol crude extract at 400 mg kg-1 body weight/day had chemo-suppression of 95.27 and 97.21% for prophylactic test as against 81.88% for the standard drug while the level of parasitemia was reduced by 80.91 and 87.64% respectively after treating for five days in the curative test as against 88.98% for the standard drug. The variations in the values of Percentage Packed Cell Volume (%PCV), erythrocyte counts, bicarbonate, creatinine, uric acid, urea and calcium level for groups treated with water and ethanol extracts were significant (p<0.05) for prophylactic and curative treatment. Histological features revealed that there were well-formed liver hepatocytes with minor injury in ethanol extract when used as prophylactic treatment. Alkaloid, Anthraquinones, Cardenoloides, Glycosides, Phenol, Phlobatanin, Reserpine, Resins and Saponin were present in the crude extract. The result of this study suggests that extracts of R. vomtitoria has antiplasmodial effects, these however supports local claims on the efficacy of the plant's leaf in the treatment malarial infections. This study has implications in future development of antimalarial drugs with little or no cytotoxic effect