Effects of Idebenone on Rat Schwann Cells with Toxicity Induced by Hydrogen Peroxide: Assessment of Molecular, Apoptosis, and Oxidative Stress Parameters.

OBJECTIVE: Schwann cells are the main cells for myelination and regeneration of peripheral nerves. Idebenone is a synthetic antioxidant used to treat central nervous system diseases. The aim of the study is to determine whether idebenone can protect Schwann cells and increase cell activity under conditions of oxidative stress caused by hydrogen peroxide (H2 O2 ) in vitro .

MATERIALS AND METHODS: In this experimental study, Schwann cells were pre-treated with various concentrations of idebenone and H2 O2 ; after determining the appropriate doses, the cells were treated with 10 μM idebenone for 48 hours and 1000 μM H2 O2 for the last two hours. The malondialdehyde (MDA) level, and activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were assessed by ELISA. Cell viability was assessed by the MTT assay. Western blot analysis was conducted to determine the expressions of myelin protein zero (MPZ) and peripheral myelin protein 22 (PMP22), and expression ratio of the Bax/Bcl-2 proteins. The percentage of cell apoptosis was evaluated by annexin V staining using flow cytometry.

RESULTS: Schwann cells under oxidative stress conditions caused by H2 O2 and treated with idebenone had increased cell viability; increased SOD, CAT, and GPx activity; and increased expressions of the MPZ and PMP22 proteins. There was a decreased level of MDA, decreased expression ratio of Bax/Bcl-2 proteins, and a decrease in the percentage of apoptotic cells stained with Annexin V.

CONCLUSION: The appropriate dose of idebenone may improve both survival and function of Schwann cells exposed to H2 O2 by reducing oxidative stress and apoptosis.