IN-VIVO EVALUATION OF 16 PLANT-EXTRACTS ON MICE INOCULATED WITH TRYPANOSOMA-BRUCEI-GAMBIENSE

After examination of the drugs used by traditional practitioners in Co te d'Ivoire, nine formulas prescribed in the treatment of African huma n trypanosomiasis (AHT) were selected for investigation. These formula s made use of 40 plants, 16 of which were studied because of their pro perties, as described in the literature, and their frequent use by pra ctitioners, The plant extracts were administered, after maceration or decoction, either orally or intraperitoneally to Swiss mice that had p reviously been inoculated with Trypanosoma brucei gambiense (Tbg), str ain MHOM/Cl/81/Dal 083. The parasitaemia in each mouse was followed fo r three consecutive days and compared with that in control mice, which had been given either a saline solution (SS: negative control) or wel l-known drugs (melarsoprol, difluoromethylornithine, and pentamidine: positive control),Our investigations led to the following conclusions. (a) None of the plant extracts revealed trypanocidal or trypanostatic activity relative to SS controls (P > 0.05), In fact the mice that re ceived the extracts died on the third day after inoculation, with 0% s urvival and an average parasitaemia of 10.8 +/- 2 x 10(7) trypanosomes /ml. (b) The treated positive controls, relative to SS, showed 100% su rvival and no parasitaemia (P < 0.05). Melarsoprol appeared to be acti ve when given orally at a dose of 3.6mg/kg body weight twice a day for 3 days. This method of testing the sensitivity of trypanosomes to pla nt extracts is easy and inexpensive, and could be applied to other are as of research on tropical diseases.