Delivery of Superoxide Dismutase 3 Gene with Baculoviruses Inhibits TNF-α Triggers Vascular Smooth Muscle Cell Proliferation and Inflammation

Background: Superoxide dismutase 3 (SOD3), recognized as a potent free radical scavenger, exhibits antioxidant, anti-inflammatory, and anti-angiogenic properties. However, the molecular mechanisms underlying the protective effects of SOD3 on the vascular smooth muscle cell during atherosclerosis remain unclear. Objectives: This study aimed to investigate the efficacy of the baculovirus expressing SOD3 gene delivery to vascular smooth muscle cells (VSMCs) and investigate whether the overexpression of SOD3 mitigates cell proliferation and migration induced by tumor necrosis factor-α (TNF- Methods: A baculoviral vector containing SOD3 cDNA (vAcMBac-CMV-IE-SOD3) was constructed and utilized to deliver the SOD3 gene into primary rat VSMCs. Cells were stimulated with recombinant TNF-α, and then cell proliferation and migration were evaluated using the bromodeoxyuridine and wound healing assay. Western blot was used to verify the expression of cell cycle regulators, cellular mediators, and proliferative biomarkers. Zymography, immunofluorescence staining, and ELISA assay were conducted to assess the expression levels of matrix metalloproteinases. Results: The results demonstrated efficient and non-cytotoxic transduction of vAcMBac- CMV-IE-SOD3 in VSMCs. SOD3 overexpression significantly suppressed cell proliferation and motility by inhibiting cell cycle regulators in TNF-α-induced cells. TNF-α elevated protein levels of phospho-ERK and phospho-Akt were reduced markedly by SOD3-overexpressing. Additionally, SOD3 overexpression attenuated the elevation of MMP-2 and MMP-9, the pro-inflammatory and proliferative biomarkers. Overall, the SOD3 gene delivery exhibited potent anti-proliferation and anti-inflammation effects on TNF-α-induced VSMCs. Conclusion: An effective SOD3 gene delivery using a recombinant baculoviral vector has been successfully established and is useful for overexpression of the SOD gene family. This approach provides new therapeutic strategies in gene therapy against atherosclerosis.