Oxidative stress and labile plasmatic iron in anemic patients following blood therapy

Abstract

AIM:To determine the plasmatic iron content and evaluate the oxidative stress (OS) markers in subjects receiving blood therapy. METHODS:Thirty-nine individuals with unspecified anemia receiving blood transfusions and 15 healthy subjects were included in the study. Anemic subjects were divided into three subgrouP: (1) those that received up to five blood transfusions (n = 14); (2) those that received from five to ten transfusions (n = 11); and (3) those that received more than ten transfusions (n = 14). Blood samples were collected by venous arm puncture and stored in tubes containing heparin. The plasma and cells were separated by centrifugation and subsequently used for analyses. Statistical analyses were performed using Kruskal-Wallis analysis of variance followed by Dunn's multiple comparison tests when appropriate. RESULTS:The eletrophoretic hemoglobin profiles of the subjects included in this study indicated that no patients presented with hemoglobinopathy. Labile plasmatic iron, ferritin, protein carbonyl, thiobarbituric acidreactive substances (TBARS) and dichlorofluorescein diacetate oxidation were significantly higher (P < 0.05), whereas total thiol levels were significantly lower (P < 0.05) in transfused subjects compared to controls. Additionally, the activity of catalase, superoxide dismutase and glutathione peroxidase were significantly lower in the transfused subjects (P < 0.05). Antioxidant enzyme activities and total thiol levels were positively correlated (P < 0.05), and negatively correlated with the levels of protein carbonyl and TBARS (P < 0.05). In contrast, protein carbonyl and TBARS were positively correlated (P < 0.05). Altogether, these data confirm the involvement of OS in patients following therapy with repeated blood transfusions. CONCLUSION:Our data reveal that changes in OS markers are correlated with levels of labile plasmatic iron and ferritin and the number of transfusions.

High ferritin in homozygous and heterozygous β-thalassemia tends to decrease oxidative stress levels

“…(19) Another study showed that SOD activity in β-thalassemia was higher than in controls, while that of GPx was lower than in controls. (20) In contrast, all patients in our study, including those with homozygous IVS1nt5 β-thalassemia and heterozygous HbE/βthalassemia had normal GPx levels. On the other hand, although SOD levels in β-thalassemia are generally normal, approximately half of the subjects had low SOD levels (Table 2).…”

Comparative In Vivo Effects of Hemoglobin-Based Oxygen Carriers (HBOC) with Varying Prooxidant and Physiological Reactivity

“…The CAT and TBARS levels at 48 hours after treatment with HBOC reveal no significant increase in the nHb group–despite the previously-documented in vitro prooxidant reactivity. Increased levels of TBARS in serum are generally associated with higher activity levels of serum catalase (CAT)[ 49 ], and this is indeed observed in Table 9 . By contrast with the TBARS and CAT measurements, the EPR spectra collected on blood samples extracted 10 minutes after administration of the HBOCs to the animals, reveal a picture closely mirroring the previously-reported in vitro prooxidant reactivity[ 39 , 50 , 51 ].Thus, nHb and HboATP display distinctly higher EPR signals, while by contrast HbRbrNROR shows no change compared to the controls other than a slight decrease in the free radical signal.…”

Alpha-lipoic acid attenuates iron-overload-induced structural changes in the liver of the laboratory mouse (Mus musculus)

“…[21] The dithiolane ring in the chemical structure of ALA confers its ability to bind redox active elements such as iron. [20,22] Since generation of ROS directly correlates with the concentration of free intracellular iron, [23] administration of ALA to iron overload patients could help chelate this free intracellular iron and thus reduce ROS generation and hepatic damage.…”