Schisandrae semen essential oil attenuates oxidative stress-induced cell damage in C2C12 murine skeletal muscle cells through Nrf2-mediated upregulation of HO-1

The aim of the present study was to examine the cytoprotective effects of Schisandrae semen essential oil (SSeo), purified from Schisandrae fructus, against oxidative stress-induced cell damage in C2C12 myoblasts. SSeo attenuated hydrogen peroxide (H2O2)-induced growth inhibition and exhibited scavenging activity against the intracellular reactive oxygen species (ROS) that were induced by H2O2. SSeo also inhibited comet tail formation, chromatin condensation and phospho-histone gamma H2A.X expression, suggesting that it prevents H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, SSeo significantly enhanced the expression of heme oxygenase-1 (HO-1) associated with the induction of nuclear factor erythroid-2-related factor 2 (Nrf2) in a time- and concentration-dependent manner. In addition, the protective effect of SSeo on H2O2-induced C2C12 cell damage was significantly inhibited by zinc protoporphyrin IX, an HO-1 competitive inhibitor, in C2C12 cells. These findings suggest that SSeo augments the cellular antioxidant defense capacity through intrinsic free radical scavenging activity and activation of the Nrf2/HO-1 pathway, thereby protecting the C2C12 cells from H2O2-induced oxidative cytotoxicity. As a result, SSeo may have therapeutic potential in the development of functional foods and as the raw material for medicines to protect against oxidative stress.