Transgenic neonatal mice expressing extra copy of extracellular superoxide dismutase (EC-SOD) had a significant reduction in ROS and improved angiogenesis in neonatal mice lung following exposure to hyperoxia, while EC-SOD knocked out mice had reduced neovascularization, increased endothelial dysfunction and worsening lung injury when compared to controls[11, 12]. Here, SOD3 is linked to endothelial dysfunction.