Introduction

Antioxidants are molecules that act to limit the oxidative damage to cells caused by reactive oxygen species (ROS). ROS are highly reactive molecules that are generated as a result of normal metabolism and are known to cause damage to a number of cellular components, including DNA, proteins, and lipids. Antioxidants act to prevent this damage by scavenging ROS before they can cause harm. Antioxidant enzymes are particularly important, as they are able to react with and neutralize ROS, as well as repair any damage that has already been done. In this article, we will review the most important antioxidant enzymes and their roles in immunology.

Superoxide Dismutase

Superoxide dismutase (SOD) is one of the most important antioxidant enzymes. It is a metalloenzyme composed of copper, zinc, and manganese, which catalyzes the dismutation of superoxide radicals (O2-) into hydrogen peroxide (H2O2) and molecular oxygen (O2). SOD is present in the cytosol and the matrix of mitochondria, and is also found extracellularly, where it acts to protect cells from the damaging effects of ROS produced by inflammation. SOD has been shown to be important for the regulation of inflammation, as well as the response of immune cells to infection.

Glutathione Peroxidase

Glutathione peroxidase (GSH-Px) is an important antioxidant enzyme that is found in the cytosol and the mitochondrial matrix. This enzyme catalyzes the reduction of hydrogen peroxide (H2O2) and organic hydroperoxides (ROOH) into water (H2O) and alcohol (ROH). GSH-Px is important for the regulation of inflammation, as it is able to reduce pro-inflammatory mediators such as prostaglandins and leukotrienes. It is also important for the regulation of immune cell function, as it is able to reduce the oxidative stress caused by ROS generated by immune cells during an immune response.

Catalase

Catalase is another important antioxidant enzyme that is found in the cytosol and the mitochondrial matrix. This enzyme catalyzes the breakdown of hydrogen peroxide (H2O2) into water (H2O) and molecular oxygen (O2). Catalase is important for the regulation of inflammation, as it is able to reduce the amount of hydrogen peroxide produced by activated immune cells. It is also important for the regulation of immune cell function, as it is able to reduce the oxidative stress caused by ROS generated by immune cells during an immune response.

Glutathione Reductase

Glutathione reductase (GSH-Rd) is an important antioxidant enzyme that is found in the cytosol and the mitochondrial matrix. This enzyme catalyzes the reduction of oxidized glutathione (GSSG) to reduced glutathione (GSH). GSH-Rd is important for the regulation of inflammation, as it is able to reduce the amount of pro-inflammatory mediators such as prostaglandins and leukotrienes. It is also important for the regulation of immune cell function, as it is able to reduce the oxidative stress caused by ROS generated by immune cells during an immune response.

Conclusion

Antioxidant enzymes are essential for the regulation of inflammation and the proper functioning of the immune system. Superoxide dismutase, glutathione peroxidase, catalase, and glutathione reductase are all important antioxidant enzymes that are found in the cytosol and mitochondrial matrix, and are involved in the regulation of inflammation and immune cell function. These enzymes are essential for protecting cells from the damaging effects of ROS, and for maintaining the health of the immune system.