Relationship Between Protein Oxidation Markers and Oxidative Stress Biomarkers

There is a general agreement (belief) that lipids are the pivotal element in inflammatory disease. One of the most studied topics is the connection between lipid oxidation and cardiovascular disease. In a very recent review, the introductory paragraphs states, after resuming the elements of the inflammatory response starting with stimulated endothelium displaying adhesive molecules for circulating leucocytes, lipid oxidation products formed by virtually every vascular cell type participate in orchestrating these processes and the inflammatory process is actively limited by activation of a resolution phase, often via generation of structurally specific oxidized lipids whose function is to orchestrate resolution of inflammation (McIntyre & Hazen 2010). Most of the knowledge involving lipid oxidation comes from “in vitro” studies and on supplementation trials with antioxidants like vitamins and anti-inflammatory drugs. Vitamins E and C are considered dietary antioxidants although mostly ex vivo measurements of lipid peroxidation have been performed (Hillstrom et al. 2003; Heinecke 2001). Quantifying “in vivo” lipid oxidation is not easy and several biomarkers of lipid peroxidation has been used like F2-isoprostanes, considered the most accurate way to measure oxidative stress “in vivo”, and as a risk factor for atherosclerosis and other diseases (Lawson et al. 1999). The secondary products of lipid peroxidation (LPO) the reactive carbonyl compounds, modify biologically essential molecules such as proteins and DNA bases (Yuan et al. 2006). Thus lipid oxidation processes in biological tissues may be more complicated since they contain a plethora of carbohydrates, proteins and lipids forming a complex matrix. In tissues, lipid oxidation can cause protein oxidation due to close interactions between lipids and proteins. LPO “in vivo” has been implicated as the underlying mechanisms in numerous disorders and diseases such as cardiovascular diseases, cancer, neurological disorders, and aging. Thus, when oxidative stress biomarkers are evaluated protein oxidation deserves consideration.