Development of an in vitro model of excess intracellular reactive oxygen species

These investigations characterize an in vitro model for generating excess intracellular reactive oxygen species (ROS). This novel model may be useful in the identification and delineation of cellular mechanisms associated with aging due to the link between age and excess oxidative events. The human cell line, MCF7, was stably transfected using the pSV3.neo plasmid housing a gene encoding the Aequorea victoria green fluorescent protein (GFP). Transfected cells were analyzed for maintenance of GFP over time, showing stability of the GFP gene. These studies demonstrate that the presence of fluorescing GFP significantly increases intracellular ROS, creating oxidative stress in these cells. Antioxidant supplementation was evaluated to determine the effectiveness of intracellular H₂O₂ reduction. The results demonstrate that supplementation with a potent antioxidant, such as reduced glutathione, protects cells from oxidative damage by decreasing intracellular concentrations of H₂O₂. This model for intracellular generation of excess ROS establishes a clear method by which the utility of antioxidant supplementation to protect against intracellularly generated reactive oxygen species may be evaluated.