Cytotoxic effects of Teucrium polium on some established cell lines

Teucrium polium (Lamaceac), part of the natural flora of Iran and the Middle East, has long been used for the treatment of diabetes, gastric inflammation, and convulsion in traditional medicine (Reishinger, 1982). Although some benefits of T polium have been claimed by researchers, very few studies have investigated the cytotoxic effects of this herb. In the current study, we investigated the cytotoxic effects of an ethanol extract of T polium on four cell lines, A549, BT20, MCF7, and PC12, by measurement of mitochondrial respiration as well as colony-forming assay. We also compared T polium cytotoxicity to paclitaxel, a known herbal anticancer agent. Our results show that the ethanol extract of T polium suppressed the growth of all tested cell lines effectively. The IC50 values for each cell line were calculated as follows: A549, 90 mu g/mL; BT20, 106 mu g/ml,; MCF-7, 140 mu g/mL; and PC12, 120 mu g/mL. T polium extract also inhibited formation of colonies in agarose efficiently. Further investigations are now needed to establish the exact mechanism of action and identify the active ingredient(s) of T polium extract in order to show its therapeutic efficacy.