The cytotoxic effects of a traditional Zulu remedy, impila (Callilepis laureola)

The traditional Zulu remedy impila (Callilepis laureola) can cause acute fatal hepatocellular necrosis, especially in children. We investigated the mechanism(s) of toxicity using HuH-7 hepatocytes. Impila tubers were extracted with boiling water and the aqueous extract was used at different concentrations to study the effects on the morphology of the cells. Flow cytometry and labelling with fluorescent antibodies to tubulin were also used. At high concentrations, necrosis occurred; however, at lower concentrations, the extracts gave rise to a variety of changes including hypercondensation of chromatin, multinucleate cells, nuclear fragmentation and apoptosis. In addition, we observed destruction of cytoplasmic tubulin. These findings give further insight into the mechanism of toxicity of herbal remedies containing atractyloside.