Supplementation of cell culture media with seleno-L-methionine increases the activity of GPxs resulting in decreased cellular phospholipid peroxidation

Selenium is an essential element for human health. It is necessary for several families of antioxidant enzymes that support of healthy cells and tissues. Per day, 55 μg of selenium is required to maximize the antioxidant potential of selenium. With this intake, antioxidant enzymes that require selenium are fully active. Deficient intake of selenium can result in decreased activity of these selenium-dependent antioxidant enzymes, increasing the susceptibility to toxicants and subsequent disease.

In the search for new drugs to cure diseases or the effects of toxicants, cell culture experiments are performed in laboratories around the world. These experiments do not require animal models, but instead typically rely on human-derived cell cultures. In many instances, cell culture experiments are conducted first to understand the mechanism of action and clinical potential of new drugs or the mechanism and severity of the impact of a toxicant. When there is more understanding of the drug or toxicant through cell culture studies, this information is used in the progression to much more focused animal studies. This thesis identified that cell culture experiments are mostly conducted under selenium-deficient conditions. This impacts the cell’s potential to deal with stress, be it physical or chemical. This deficiency may result in overestimation of the toxicity of a stressor. Simply increasing the availability of selenium to cells will maximize the activity of selenium-dependent antioxidant enzymes, just like the daily recommended intake of humans. This will lead to better information from cell culture studies, increasing the value of data derived from these types of experiments.