Reduced Glutathione Peroxidase Activity Predicts Increased Cardiovascular Risk Following an Acute Coronary Syndrome

Glutathione peroxidase (GPx) is a family of antioxidant enzymes that reduce reactive oxygen species (ROS), thereby constituting a primary defence system against oxidative stress. Of the five characterised isoforms of GPx found in mammals, GPx1 is the predominant intracellular form and GPx3 is the predominant form found in the extracellular space1. Experimental studies have demonstrated that deficiencies in GPx1 activity result in abnormal vascular and cardiac structure and function2. Deficiencies in the GPx3 enzyme lead to a pro-thrombotic state in mouse models3. Clinical case studies have demonstrated an association between decreased levels of plasma GPx activity and familial arterial thrombosis4. In stable coronary artery disease, patients with lower levels of GPx1 activity have a higher incidence of major adverse cardiovascular events (MACE)5.