Role of Antioxidants in Autoimmune Diseases

Abstract

Free radicals and related compounds are commonly classified together as reactive oxygen species (ROS) to show their role in changing oxidative status within the cell. Cells commonly have different mechanisms to protect the body against damages created by free radicals. Problems are seen when synthesis of ROS is faster than their removal by the antioxidant protection mechanisms, or when the latter is impaired. This imbalance between cellular synthesis of ROS and the inability of cells to protect against them is known as oxidative stress. Oxidative stress can make cellular damage and then cell death due to the ROS oxidize cardinal cellular parts, such as lipids, proteins, and DNA. Antioxidants are exogenous (natural or synthetic) or endogenous factors play their role in several pathways including diminish of O2, scavenging ROS or their precursors, suppressing their production and binding metal ions required for catalysis of ROS production. The natural antioxidant mechanism can be classified into two major types: enzymatic (e. g., catalase, superoxide dismutase,) and nonenzymatic or the low molecular weight antioxidants (LMWA). Therefore, in this book, we aimed to shed a light on the role of antioxidants in autoimmune diseases.