Phlomis species protects the cells from oxidative stress by upregulating catalase enzyme expression

Recently, interest in the pharmacological effects of plants has increased and studies on bioactive compounds have intensified. In this study, we aimed at evaluating the antioxidant and neuroprotective potential of Lamiaceae plants including Stachys lavandulifolia, Salvia verticillata, Phlomis herba venti sp. pungens and Phlomis sieheana in both cellfree systems and the cell culture model. Methanol extracts of the aerial parts of these plants, cultivated in Elazig, Turkey were carried out. Antioxidant activity assays (ABTS and DPPH) and total phenolic and flavonoid contents of the extracts were measured. Next, the effects of methanol extracts on cell viability and catalase protein levels were investigated in hydrogen peroxide induced oxidative stress model. DPPH radical scavenging activities were determined with the IC50 value of 31.36 +/- 0.25, 30.44 +/- 0.19, 30.16 +/- 0.08 and 56.54 +/- 0.93 for Stachys lavandulifolia, Salvia verticillata, Phlomis herba venti sp. pungens and Phlomis sieheana, respectively. ABTS radical scavenging activities were determined as 6.38 +/- 1.48, 16.93 +/- 0.68, 5.97 +/- 4.04 and 2.28 +/- 0.51. The highest cellular protection and catalase expression were determined in Phlomis-treated cells against H2O2 (p<0.05). On the other hand, no statistically significant change in cell viability was observed when the extracts were compared with each other. Our findings support the neuroprotective and antioxidant potential of these four Lamiaceae plants, particularly Phlomis species.