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

Increased Oxidative Stress in Acute Myeloid Leukemia Patients after Red Blood Cell Transfusion, but Not Platelet Transfusion, Results Mainly from the Oxidative/Nitrative Protein Damage: An Exploratory Study

Chronic oxidative stress (OS) can be an important factor of acute myeloid leukemia (AML) progression; however, there are no data on the extent/consequence of OS after transfusion of packed red blood cells (pRBCs) and platelet concentrates (PCs), which are commonly used in the treatment of leukemia-associated anemia and thrombocytopenia. We aimed to investigate the effects of pRBC/PC transfusion on the OS markers, i.e., thiol and carbonyl (CO) groups, 3-nitrotyrosine (3-NT), thiobarbituric acid reactive substances (TBARS), advanced glycation end products (AGE), total antioxidant capacity (TAC), SOD, GST, and LDH, in the blood plasma of AML patients, before and 24 h post-transfusion. In this exploratory study, 52 patients were examined, of which 27 were transfused with pRBCs and 25 with PCs. Age-matched healthy subjects were also enrolled as controls. Our results showed the oxidation of thiols, increased 3-NT, AGE levels, and decreased TAC in AML groups versus controls. After pRBC transfusion, CO groups, AGE, and 3-NT significantly increased (by approximately 30, 23, and 35%; p < 0.05, p < 0.05, and p < 0.01, respectively) while thiols reduced (by 18%; p < 0.05). The PC transfusion resulted in the raise of TBARS and AGE (by 45%; p < 0.01 and 31%; p < 0.001), respectively). Other variables showed no significant post-transfusion changes. In conclusion, transfusion of both pRBCs and PCs was associated with an increased OS; however, transfusing the former may have more severe consequences, since it is associated with the irreversible oxidative/nitrative modifications of plasma proteins.

Occult Kidney Dysfunction in Children With Transfusion-Dependent Thalassemia

Background: Thalassemia is the commonest hemoglobinopathy in Southeast Asia. Kidney dysfunction is an underreported sequelae in children with thalassemia. We conducted a retrospective study to identify the prevalence of and predisposing factors for kidney dysfunction in children with transfusion-dependent thalassemia (TDT). Method: Abnormal kidney function was defined as children with a glomerular filtration rate (GFR) of <90 ml/min/1.73 m² or a decline in GFR of >20 ml/min/1.73 m² or presence of nephrotic range proteinuria within 3 years of commencing regular (every ≤6 weeks) red cell transfusion. Data analyzed were age at diagnosis of thalassemia, number of transfusion-years, iron chelation therapy, serum ferritin, and pre-transfusion hemoglobin levels. Results: Eighty-one children were studied. Mean age was 11.72 ± 5.275 years. Thirty out of 81 (37%) demonstrated abnormal kidney function. Evidence of glomerular hyperfiltration was seen in 29/81 patients (25.85%) at their last clinic visit. This fraction was doubled [48/81 (59.3%)] when the cohort was tracked back by 3 years from the last clinic encounter. Age at diagnosis (RR, 1.157; 95% CI, 1.014-1.319; p = 0.03) and duration of receiving transfusions (RR, 0.984; 95% CI, 0.974-0.994; p = 0.001) were associated with increased risk of developing abnormal kidney function. Conclusion: Abnormal kidney function in children with TDT may be overlooked by medical personnel without active screening measures. Children receiving regular red cell transfusions require systematic surveillance to enable early detection of kidney dysfunction and timely implementation of appropriate therapeutic interventions.

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

A series of hemoglobin-based oxygen carrier candidates (HBOC), previously noted for their differences in prooxidative and physiological reactivity, were compared in terms of the negative effects displayed upon injection in Wistar rats. At the concentrations tested, antioxidant strategies based on albumin as well as based on rubrerythrin appear to offer observable physiological advantages.

Effects of Transportation on Antioxidant Status in Cynomolgus Macaques (Macaca fascicularis)

To evaluate the effects of transportation on oxidative stress in cynomolgus monkeys, we measured serum levels of reduced glutathione (GSH), malondialdehyde, and protein carbonyl (PC) and the activities of total antioxidant capacity (TAOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase in cynomolgus macaques before transportation (day 0), on the day of arrival (day 1), and on days 7, 14, and 21 after transportation. Compared with that on day 0, TAOC and catalase activities on days 1, 7, and 14 after transportation were significantly decreased, reached their nadirs on day 7, and increased thereafter to reach their pretransportation levels by day 21 after transportation. Compared with day 0 levels, mean SOD activity and GSH concentration were decreased significantly on day 1; they thereafter increased to reach their pretransportation measures by day 7 after transportation. In contrast, PC and malondialdehyde concentrations in serum and the activity of GSH-Px were increased on day 1 compared with day 0 and thereafter decreased to reach their pretransportation levels by day 14 after transportation. In summary, GSH, TAOC, catalase, and SOD levels decreased and malondialdehyde, PC, and GSH-Px concentrations increased in cynomolgus macaques after transportation. These results suggest that transportation might imbalance oxidant and antioxidant levels to create excess oxidative stress in cynomolgus macaques. Therefore, cynomolgus macaques should have at least 21 d to recover after transportation and regain their healthy status.