3.3. Neuroprotective effect of H. rhamnoides on H2O2 induced
cytotoxicity
Neuroprotective activity of H. rhamnoides was assessed by
subjecting IMR32 cells to 24 h H2O2 (250 lM) challenge,
which were pretreated with different concentrations of H.
rhamnoides extract for 24 h (3.2–100 lg/ml). The cell death
was determined using propidium iodide staining assay. An
increase in cell viability was observed in treated cells compared
to H2O2 controls in a dose dependent manner as illustrated in
Fig. 3. 100 lg/ml was found to be the effective concentration;
similar results were obtained from MTT assay (results not
shown). A significant increase in cell viability was observed
at 100 lg/ml of the plant extract.