MitoQ alleviates prion-induced neurodegeneration by modulating DRP1- and OPA1-mediated mitochondrial dynamics

Prion diseases are a group of fatal neurodegenerative disorders with no effective treatments. MitoQ, a mitochondria-targeted antioxidant, has shown promise in treating mitochondrial redox-related diseases; however, its role in prion diseases remains unclear. In this study, we demonstrate that MitoQ significantly alleviates PrP^106-126-induced oxidative stress, mitochondrial dysfunction, and apoptosis in mouse neuroblastoma N2a cells. Specifically, MitoQ reduces intracellular and mitochondrial reactive oxygen species (ROS) accumulation, enhances total antioxidant capacity (T-AOC) and the glutathione (GSH)/oxidized glutathione (GSSG) ratio, restores oxygen consumption rate (OCR), mitochondrial membrane potential (MMP) and intracellular ATP levels, and prevents cytochrome c release and caspase 3 activation. Mechanistically, MitoQ downregulates dynamin-related protein 1 (DRP1) phosphorylation at Ser616 and reduces mitochondrial DRP1 accumulation, while upregulating optic atrophy 1 (OPA1), thereby improving the mitochondrial dynamics imbalance induced by PrP^106-126. Notably, DRP1 overexpression or OPA1 knockdown abolishes these protective effects, resulting in persistent oxidative stress, mitochondrial dysfunction, and apoptosis. These findings suggest that MitoQ alleviates prion-induced neurodegeneration by modulating DRP1- and OPA1-mediated mitochondrial dynamics, highlighting its therapeutic potential in prion diseases.