TWENTY EIGHT DAYS ORAL ADMINISTRATION ASSESSMENT OF HYDNORA AFRICANA THUNB. AQUEOUS ROOT EXTRACT ON KEY METABOLIC MARKERS OF WISTAR RATS

Hydnora africana Thumb (Hydronaceae) is a parasitic flowering plant with significant global ethnomedicinal value. This study evaluated the toxicological effects of the acute and sub-acute dosing treatments of the aqueous root extract of Ha in male and female wistar rats using OECD guidelines 423 and 407. For the acute study, the extract was administered to the animals at single oral graded doses of 1000, 2000 and 5000 mg/kg body weight (b.w.) and subsequently observed for 14 days, while it was given at 250, 500, and 1000 mg/kg b.w. once daily for 28 days in the sub-acute testing. Clinical toxicity signs, behavioral changes, hematological and biochemical parameters were then monitored and evaluated. The result revealed that, at a limit dose of 5000 mg/kg b.w., the extract neither had treatment – mediated symptoms of toxicity nor mortality over the 14 days observation period. In the sub-acute study and particularly for the male rats, the extract significantly increased the serum levels of the erythrocytes and haemoglobin, while the platelet counts increased dose-dependently in both male and female treated animals. The non-significant (p>0.05) effect on other evaluated parameters and the no treatment-induced abnormalities in the relative organ weights of the animals indicated that it is unlikely to be toxic to the investigated organs and suggests that its oral median lethal dose is approximately higher than 5000 mg/kg. From the data presented in this study, it could be logically inferred that aqueous root extract of H. africana is non-toxic at the tested doses and within the period of exposure.