Background: Oxidative stress plays a key role in various conditions, including cancer, cardiovascular and neurodegenerative diseases, diabetes, chronic inflammation, and organ transplantation. In transplantation, ischemia-reperfusion (I/R) injury poses a major threat to graft survival. During reperfusion, the sudden return of oxygen triggers a surge in reactive oxygen (ROS) and nitrogen species (RNS). These overwhelm cellular antioxidants, causing mitochondrial dysfunction and oxidative damage to DNA, proteins, and lipids, leading to lipid peroxidation and inflammation via pathways like NF-κB. Elevated Fe²⁺ levels further drive ROS production through Fenton reactions, intensifying mitochondrial damage and respiratory failure. This cascade results in tissue injury, reduced cell viability, and impaired organ function.
Methods: We developed transgenic pigs and conducted preliminary in vitro studies to assess the function of a novel transgene in protecting against oxidative stress-induced cell death pathways, including apoptosis, necrosis, and ferroptosis. Additionally, we evaluated its effects on mitochondrial membrane integrity, superoxide production, respiratory capacity, and recovery following oxidative stress.
Results: Our analyses showed reduced cell death responses, including lower apoptosis marked by decreased caspase-3 and -7 activity, inhibition of mitochondrial permeability transition pore (MPTP)-mediated necrosis, and reduced lipid peroxidation, the terminal step of ferroptosis. Additionally, mitochondrial superoxide production was decreased, while respiratory function and recovery following oxidative stress were notably enhanced.
Conclusion: This novel pig model demonstrates that novel transgenes can effectively reduce oxidative damage in vitro by modulating intracellular antioxidant defenses, mitochondrial function, and ROS production. These transgenes could play a key role in improving long-term outcomes in future xenotransplantation.