Studies on Oxidative Stress in Erythrocytes of Stored Blood

Abstract

The assessment of total antioxidant capacity (TAC) provides an overview into the interactions between enzymatic and non-enzymatic defenses in erythrocytes. The cupric ion reducing antioxidant capacity - bathocuproinedisulfonic acid disodium salt (CUPRAC-BCS) method has been employed to assess total antioxidant capacity of human plasma and urine (Campos et al., 2009), while the antioxidant activity (AOA) method has been utilized in determining the antioxidant capacity of human fluids such as saliva, tears and urine (Koracevic et al., 2001). These two assays focus on assessing the levels of non-enzymatic antioxidants. newlineErythrocytes are highly susceptible to modifications due to: (a) their constant presence in an environment of oxygen (prone to oxidative stress and hemoglobin autoxidation) (Misra and Fridovich, 1972b), (b) absence of nucleus and other organelles (no repair or macromolecule generation machinery) and (c) high concentration of substrates prone to damage (PUFAs and proteins) (Kucukatay et al., 2012). Storage lesion due to oxidative stress is vital, as a large part of the oxidative damage is irreversible, unlike the biochemical changes. There are many markers which elucidate the damaging effects of OS in formation of the storage lesion. It is newline37 newlineevident that a multitude of changes occur in the erythrocytes during storage, which contribute collectively to gradual RBC degradation leading to release of hemoglobin and cytosolic contents and hemolysis. An insight into the changes that occur during storage in the erythrocyte, mainly due to oxidative stress, will facilitate effective strategies for the protection of erythrocytes against oxidative damage. newline