Trx expression in the sputum of COPD patients is positively correlated with the degree of hypoxia.261 Mice that overexpress human Trx can effectively inhibit a CS-induced emphysema and pulmonary inflammation.262 Intraperitoneal injection of Trx suppress a smoke-induced murine pulmonary inflammation by inhibiting the production and release of cytokines, inflammatory mediators, chemokines and ROS.263 Trx inducer increases the Trx expression in murine lung tissue and improves lung injury.261 Recent research has also shown that inhaled Trx also reduces a smoke-induced chronic lung injury. Here, TXN is linked to chronic obstructive pulmonary disease.