Oxidative stress can be defined as the imbalance of the redox state of a certain system including living one (organelle, cell, organ/tissue), which excessively produces reactive oxygen and/or reactive nitrogen species (ROS/RNS) that exceed the capacity of the antioxidant defense system, which have the ability to slow down or even prevent the oxidative damage of macromolecules. Oxidative stress is a pathogenic mechanism of a large variety of diseases, including pulmonary one.