Characterization of New Serum Biomarkers of Ferroptosis in Patients With COPD With/Without Risk of Cardiovascular Events. Pathophysiological Implications, Diagnostics and Prognoses. FerrEPOC Study

Iron metabolism is related to several biochemical and functional factors that have a mayor impact in chronic obstructive pulmonary disease (COPD) such as hypoxia, hypercapnia, oxidative stress, chronic inflammation, cellular senescence, sarcopenia and ferroptosis. Ferroptosis is a specific form of cell death induced by excess intracellular free iron that generates lipid peroxidation of cell membranes, with subsequent cell death. The existence of excess ferroptosis in COPD due to tobacco smoke has been widely demonstrated in vitro both in respiratory tissue and in skeletal muscle. Iron and lipid metabolism disorders are an essential part of the pathogenesis of ferroptosis. These disorders have also been related to diseases that occur concomitantly with COPD, such as cardiovascular diseases. Recently, new genes related to iron metabolism that are involved in the development of ferroptosis have been identified. Proteins related with these genes have not been studied in vivo in the context of COPD and cardiovascular diseases. Some of them are purely intracellular in expression, but the expression of some of them can be measured in blood using methods available to any clinical laboratory. After an exhaustive study of the literature, we have selected a small group of circulating proteins expressed in DEGs (Differentially Expressed Genes) related to ferroptosis that overlap with the DEGs of COPD and the DEGs of atherosclerosis to evaluate the relationship between these molecules and clinical variables of COPD and their potential utility in identifying the risk of exacerbations, admissions, and cardiovascular events in COPD. This study could identify a trait in COPD useful for selecting patients at greater risk of exacerbation due to the relationship between ferroptosis and systemic inflammation and oxidative stress, cardiovascular risk and, in general, a worse prognosis of the disease. In addition, the identification of this trait can have important therapeutic implications.