Tocopherol attenuates the oxidative stress of BMSCs by inhibiting ferroptosis through the PI3k/AKT/mTOR pathway

Abstract

Oxidative stress can induce bone tissue damage and the occurrence of multiple diseases. As a type of traditional medicine, tocopherol has been reported to have a strong antioxidant effect and contributes to osteogenic differentiation. The purpose of this study was to investigate the protective effect of tocopherol on the oxidative stress of rat bone marrow-derived mesenchymal stem cells (BMSCs) and the underlying mechanisms. By establishing an oxidative stress model in vitro, the cell counting kit-8 (CCK-8), reactive oxygen species (ROS) analysis, Western blot (WB), real-time PCR (RT-PCR), alkaline phosphatase (ALP) staining, and Alizarin Red staining (ARS) evaluated the effects of tocopherol on the cell viability, intracellular ROS levels, and osteogenic differentiation in BMSCs. In addition, ferroptosis-related markers were examined via Western blot, RT-PCR, and Mito-FerroGreen. Eventually, the PI3K/AKT/mTOR signaling pathway was explored. We found that tocopherol significantly maintained the cell viability, reduced intracellular ROS levels, upregulated the levels of anti-oxidative genes, promoted the levels of osteogenic-related proteins, and the mRNA of BMSCs stimulated by H2O2. More importantly, tocopherol inhibited ferroptosis and upregulated the phosphorylation levels of PI3K, AKT, and mTOR of BMSCs upon H2O2 stimulation. In summary, tocopherol protected BMSCs from oxidative stress damage via the inhibition of ferroptosis through the PI3K/AKT/mTOR pathway.