Thioredoxin reductases are enzymes that play a crucial role in maintaining the balance of redox reactions within cells. They help convert oxidized thioredoxin into its reduced form, which is essential for various cellular processes, including DNA synthesis and the regulation of oxidative stress. These enzymes are found in many organisms, from bacteria to humans, and are vital for cellular health. By facilitating the transfer of electrons, thioredoxin reductases contribute to the detoxification of harmful reactive oxygen species, thereby protecting cells from damage and supporting overall metabolic functions.