PRDX2-PARK7 Axis Alleviates Ang II-Induced Iron-Dependent Oxidative Injury and Ferroptotic Phenotypic Changes in Vascular Smooth Muscle Cells In Vitro

Background: Oxidative stress and ferroptosis-associated pathways have recently emerged as important mechanisms contributing to vascular smooth muscle cell (VSMC) injury; however, their molecular regulation remains poorly understood. This study aimed to determine whether the peroxiredoxin 2 (PRDX2)-Parkinsonism-associated deglycase (PARK7) axis protects against angiotensin II (Ang II)-induced VSMC injury and to elucidate the underlying mechanism.Methods: In vitro injury models were established using human VSMCs exposed to Ang II. PRDX2 was overexpressed using plasmid transfection, whereas PARK7 was silenced by short hairpin RNA. Cell viability and proliferation were assessed using Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2′-deoxyuridine (EdU) assays, respectively, and apoptosis was evaluated by flow cytometry. Ferroptosis-related parameters, including intracellular iron accumulation, reactive oxygen species (ROS) levels in culture supernatants, and glutathione (GSH) depletion, were assessed. Western blot analysis was performed to quantify the expression levels of PARK7, nuclear factor erythroid 2-related factor 2 (Nrf2), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and VSMC phenotypic markers, including alpha-smooth muscle actin (α-SMA), smooth muscle protein 22-alpha (SM22-α), and osteopontin (OPN). Protein-protein interactions were predicted using bioinformatics databases and validated by co-immunoprecipitation (CO-IP).Results: Ang II stimulation markedly impaired VSMC viability and proliferation, promoted apoptosis, induced iron-dependent oxidative stress with dysregulation of ferroptosis-associated markers, and triggered phenotypic switching from a contractile to a synthetic state. PRDX2 overexpression significantly improved cell viability (p < 0.001), restored proliferation (p < 0.05), reduced apoptosis (p < 0.001), decreased iron and ROS levels in culture supernatants (p < 0.001), and restored GSH content (p < 0.001). Moreover, PRDX2 overexpression increased the expression of PARK7, Nrf2, SLC7A11, GPX4, α-SMA, and SM22-α (p < 0.05), while reducing OPN expression (p < 0.001). CO-IP analysis confirmed a direct interaction between PRDX2 and PARK7. Importantly, PARK7 knockdown attenuated the protective effects of PRDX2 overexpression against ferroptosis-associated changes and phenotypic maintenance.Conclusion: The PRDX2-PARK7 axis alleviates Ang II-induced VSMC injury by attenuating iron-dependent oxidative stress and modulating ferroptosis-associated phenotypic changes, accompanied by the restoration of Nrf2, SLC7A11, and GPX4 expression levels.