Antioxidants in respiratory diseases: Basic science research and therapeutic alternatives

Abstract

The human body makes free radicals all the time for useful purposes. The antioxidant levels and control systems recover any injury occurring. The enzymes that repair DNA damage by free radicals are especially important. Inhaled reactive oxidant species (ROS) and those endogenously formed by inflammatory cells constitute an increased intrapulmonary oxidative burden. In many diseases, the balance between oxidants and antioxidants (redox balance) is altered causing severe consequences. He proceeds to review the pathophysiological mechanisms by which free radicals generate various types of stress, such as oxidative stress, nitrative, carbonyl, inflammatory and stress of the endoplasmic reticulum. Later we discuss how these different types of stress affect respiratory functions in diseases such as chronic obstructive pulmonary disease (COPD), bronchial asthma (BA), bronchiectasis, and idiopathic pulmonary fibrosis (IPF). Finally, the role that various strategies to increase lung antioxidants and potentially beneficial effects of antioxidant therapy in the course of the disease are discussed.