THE SUB-CHRONIC TOXICITY OF METHANOL EXTRACT OF Leptoderris trifoliolata (ROOT) AND Uraria picta (LEAF)

ABSTRACT

Medicinal plants are sources of natural products which play pivotal role as drug lead compounds some of which forms the basis for treating various human diseases. However, the local usage of these plants may sometimes come with some safety issues. Leptoderris trifoliolata and Uraria picta, members of the Fabaceae family. This study evaluated the sub-chronic toxicity of methanol extract of Leptoderris trifoliolata (root) and Uraria picta (leaves) in Wistar rats. The study involved the extraction of the plants’ leaves using methanol as solvent. The resulting extracts were evaluated in a 28-day sub-chronic study using standard protocols. Sets of female albino rats of the Wistar strain weighing 80 ± 100 kg were used for the study. Various concentrations of the methanol extracts of the plants were administered to the animals orally, once daily by means of a gavage. On the 28th day, the animals were fasted overnight, sacrificed, and the relevant tissue samples were collected for analysis. Results showed non-significant (p > 0.05) differences in haematological indices of the extracts-treated groups compared with control. There were non-significant (p > 0.05) differences in urea level of the extracts treated groups relative to control values; the exceptions were the groups administered U. picta extract (300mg/kg and 2000mg/kg) which showed significant (p < 0.05) increase in creatinine levels as well as the L. trifoliolata (50, 300 and 2000 mg/kg) groups with significant (p < 0.05) reduction in their creatinine levels in contrast to control. Non-significant (p > 0.05) changes in serum Na+ , P+ and Cllevels in all the groups was observed. L. trifoliolata (1000 mg/kg) and U. picta (1000 mg/kg) groups showed significant (p < 0.05) increase in total cholesterol and triacylglycerol levels, respectively while other test groups remained normal in contrast to the control. Serum HDL cholesterol level was only high in the L. trifoliolata (1000 mg/kg) exposed rats while LDL cholesterol level increased significantly in U. picta (50, 300, and 2000 mg/kg) and L. trifoliolata (100 mg/kg) administered rats. The AST activity was only increased in U. picta (50 mg/kg) group; ALT was however high in U. picta (1000 and 2000 mg/kg) and L. trifoliolata (2000 mg/kg) groups compared to the control. Total bilirubin remained normal in all the groups except for the L. trifoliolata (2000 mg/kg). The in vivo antioxidant potential of the extracts including SOD, catalase, GPx and GSH were observed to increase in the three tissues assayed for while that of MDA remained normal. Histopathological examination showed no evidence of abnormalities in the extracts administered groups when compared with the control.