PRDX3 (peroxiredoxin 3) is a mitochondrial thiol-specific peroxidase that serves as the major sink for hydrogen peroxide and other hydroperoxides within mitochondria, catalyzing their reduction to water and alcohols 1. The protein exhibits dual subcellular localization in both the mitochondrial matrix and intermembrane space, achieved through sequential proteolytic processing by mitochondrial peptidases during import 1. PRDX3 plays a critical protective role against oxidative stress by maintaining cellular ROS balance and preventing mitochondrial dysfunction 23. During ferroptosis, mitochondrial lipid peroxides trigger PRDX3 hyperoxidation, causing its translocation from mitochondria to plasma membranes where it inhibits cystine uptake, serving as a specific ferroptosis marker 4. The protein demonstrates therapeutic relevance across multiple pathological conditions, including protection against neurodegeneration in Parkinson's disease through antioxidant gene therapy 5, mitigation of pulmonary fibrosis by preventing alveolar epithelial cell senescence 2, and modulation of microglial polarization in uveitis 6. PRDX3 mutations are associated with punctiform and polychromatic pre-Descemet corneal dystrophy 7. The protein's stabilization by prohibitin contributes to glioblastoma therapeutic resistance by suppressing mitochondrial ROS in cancer stem cells 3.