Antioxidant effect and protective effect of <i>Salvia plebeia</i> extract against H₂O₂-induced oxidative stress in neuronal cell

Neuronal cells from oxidative stress are caused by the overproduction of reactive oxygen species or dysfunction of antioxidant system, which are closely associated with neurodegenerative diseases.Salvia plebeia R. has been used as traditional medicine for treating asthma or respiratory symptoms.In this study, the antioxidant activity and protective effect of S. plebeia ethanol extract (SPE) on SH-SY5Y cells induced by oxidative stress were investigated.As a result, the total phenol content was 226.6119.84mg GAE/g, and total flavonoid content was 46.300.71mg QE/g in SPE.SPE showed strong DPPH radical scavenging efficacy at concentrations of 75 and 100 g/ mL, showing 82.836.82 and 89.137.60%,respectively.SPE also scavenged ABTS radicals, in particular, 100 g/mL SPE showed the highest ABTS radical scavenging activity, showing 90.350.34%.SPE showed high OH radical elimination at concentrations of 25, 50, 75, and 100 g/mL, indicating over 90% scavenging activity.Treatment with hydrogen peroxide (H 2 O 2 , 500 M) induced neuronal cell death compared to non-treated cells.However, SPE treatment significantly increased cell viability and decreased the amount of lactate dehydrogenase release.Furthermore, total apoptotic cells were decreased by treatment with SPE.These findings suggest that SPE possesses antioxidant properties and neuroprotective effects against oxidative stress and may partially prevent neurodegenerative diseases.