ZIKV NS3 Disrupts the Nrf2 Antioxidant Defense and Mediates Vascular Smooth Muscle Cell Damage and Vascular Dysfunction

Zika virus (ZIKV) infection has been associated with vascular complications, yet the mechanisms underlying ZIKV-induced vascular injury, particularly after viral clearance from the bloodstream, remain poorly understood. This study investigated vascular damage before and after viral clearance during ZIKV infection and examined the role of ZIKV non-structural protein -3 (NS3) in oxidative stress–mediated vascular dysfunction. ZIKV infection models were established in interferon-α/β receptor–deficient A129 mice and immunocompetent non-human primates Macaca Leonina. Vascular structure and function were assessed by histopathology, transmission electron microscopy, immunofluorescence, and vascular reactivity assays. Primary murine vascular smooth muscle cells (mVSMCs) were used for mechanistic studies. Transcriptomic analysis, antioxidant pathway evaluation, and co-immunoprecipitation (Co-IP) assays were performed to elucidate NS3-associated molecular mechanisms. In A129 mice, ZIKV persisted in the bloodstream and caused progressive vascular injury. In contrast, in immunocompetent Macaca leonina, viral RNA in the bloodstream declined to undetectable levels by 15 days post-infection (DPI); however, viral RNA and envelope protein remained detectable in vascular tissues at 63 DPI, indicating the formation of a vascular viral retention. In both models, ZIKV infection induced sustained endothelial injury, enhanced vascular smooth muscle cells (VSMCs) migration, and impaired vascular reactivity. Mechanistically, NS3 interacted with nuclear factor erythroid 2-related factor 2 (Nrf2), inhibited its nuclear translocation, and suppressed the Nrf2/Kelch-like ECH-associated protein 1/glutathione peroxidase 4 (Nrf2/KEAP1/GPX4) antioxidant signaling pathway, resulting in increased oxidative stress. Restoration of Nrf2 activity significantly improved antioxidant capacity and attenuated vascular injury.