Abstract

Human serum albumin, a negative acute phase reactant and marker of nutritive sta-tus, presents at high concentrations in plasma. Albumin has always been used in many clinical states especially to improve circulatory failure. It has been showed that albumin is involved in many bioactive functions such as regulation of plasma osmotic pressure, binding and transport of various endogenous or exogenous com-pounds, and finally extracellular antioxidant defenses. Molecules like transferrin, caeruloplasmin, haptoglobin, uric acid, bilirubin, á-tocopherol, glucose, and albu-min constitute extracellular antioxidant defenses in blood plasma but albumin is the most potent one. Most of the antioxidant properties of albumin can be attri-buted to its unique biochemical structure. The protein possesses antioxidant proper-ties such as binding copper tightly and iron weakly, scavenging free radicals, e.g., hypochlorous acid (HOCl) and Peroxynitrite (ONOOH) and providing thiol group (-SH). Whether it is chronic or acute, during many pathological conditions, biomarkers of oxidative protein damage increase and this observation continues with considerable oxidation of human serum albumin. There is an important necessity to specify its interactions with Reactive Oxygen Species. Generally, it may lower the availability of prooxidants and be preferentially oxidized to protect other macromolecules but all these findings make it necessary that researchers give a more detailed explanation of albumin and its relations with oxidative stress.

DOI: 10.7754/Clin.Lab.2012.121115