Thioredoxin Reductase is an enzyme that plays a crucial role in maintaining the balance of redox reactions within cells. It helps to regenerate thioredoxin, a small protein that acts as an antioxidant, by converting oxidized thioredoxin back to its reduced form. This process is essential for protecting cells from oxidative stress and maintaining cellular function. The enzyme uses NADPH as a source of reducing power, facilitating the transfer of electrons. Thioredoxin Reductase is found in various organisms, including bacteria, plants, and animals, highlighting its importance in cellular metabolism and defense against oxidative damage.