Determinação de Parâmetros Oxidativos e Bioquímicos em Indivíduos Multitransfundidos

Abstract

Iron is an essential element that participates in several metabolic activities of cells. However, its excess is believed to be a major cause of iron-induced oxidative stress in subjects undergoing blood transfusion therapy. Thus, the objective this study was to determine the plasmatic iron content and evaluate the oxidative stress markers and the activity of the antioxidant enzymes in anemic subjects receiving repeated blood transfusions in the past year, comparing with healthy controls (blood donors). A total of 50 individuals multitransfused and 20 controls (no transfusion), divided into 4 groups: control group (n=20); group that received up to five (<5 transfusions) blood transfusions (n=15); group that received from five up to ten (5 – 10 transfusions) blood transfusions (n=17); group that received over than ten (>10 transfusions) blood transfusions (n=18). Plasmatic iron and oxidative stress markers (protein carbonyl, TBARS and DCFH-DA oxidation) were significantly higher, whereas total -SH levels was significantly lower in subjects receiving blood transfusion compared to controls. Additionally, the activity of the antioxidant enzymes (CAT, SOD and GPx) were significantly lower in the multitransfused subjects whem compared to controls subjects. Moreover, we found statistically significant correlations between the number of transfusions, the plasmatic iron content, the oxidative stress markers (protein carbonyl, TBARS, and total –SH) and the activity of the antioxidant enzymes (CAT, SOD, and GPx). In summary, our data confirm the involvement of oxidative stress in anemic patients after repeated blood transfusions. Additionally, we found that the changes in the oxidative stress markers are significantly correlated with both iron content and number of blood transfusions.