Antioxidant and cytotoxic potentials of the methanolic extract of Teucrium persicum Boiss. in A-375 melanoma cells

Teucrium persicum is an Iranian endemic plant used in Iranian traditional medicine. The total phenolic and total flavonoid contents, and antioxidant potential of the methanolic extract of T. persicum were determined. The MTT test was used to evaluate the inhibitory effect of the extract on the viability of A-375 cells. The clonogenic, micronucleus formation, and acridine orange/ethidium bromide staining methods were used to evaluate the survival and proliferation of A-375 cells. Apoptosis was evaluated by using DNA fragmentation assay and measuring the activity of caspase 3/7. To study the effect of the extract on the migration of A-375 cells, the in vitro wound-healing (scratch) assay was employed. The average total phenolic and flavonoid contents and antioxidant properties of the extract were 6.97±0.011 mg Ellagic acid (EGA)/g, 46.83±0.0019 mg of the ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline; EQ)/g of dried extract, and 10±0.002 μg/ml, respectively. The IC50 value of the T. persicum methanolic extract was 13 μg/ml for 48 hr. The DNA fragmentation pattern and the activity of caspase3/7 suggested that the reduction of the cell viability may be due to apoptosis induction. Microscopic observations showed nuclear condensation, a considerable increase in micronuclei formation, and inhibition of the colony formation in A-375 cells treated with 7 μg/ml to 15 μg/ml of the extract. Wound-healing assay supported the anti-migration activity of the extract. T. persicum has significant antioxidant and cytotoxic properties. Surely, more detailed molecular and biochemical studies are needed to find the mechanism(s) behind these effects.