Total Oxidant and Antioxidant Capacity in Patients with Transfusion Dependent and Nondependent Beta Thalassemia

Abstract

Background: The patients with β-thalassemia are usually under oxidative stress due to iron overload as a result of ineffective erythropoiesis and repeated transfusions. The endogen (uric acid, indirect bilirubin) and exogenous (ascorbic acid and vitamin E) antioxidants protect the cells from oxidative damage. The evaluation of antioxidant defense system can be easily done by measuring serum total antioxidant capacity. The aim of this study is to investigate the total oxidant (TOC) and antioxidant capacity (TAC) of patients with transfusion dependent (TDT) and nondependent (NTDT) β -thalassemia. Methods: Fifty eight patients (age range 3-59; median age 24 years) with β-thalassemia (16 nontransfusion dependent, 42 transfusion dependent) who were followed-up by Istanbul Medical Faculty Thalassemia Center were enrolled in this study. The sex and age matched 25 healthy subjects were used as control group. The total oxidant and antioxidant capacity were measured by Rel Assay Diagnostics, Total Oxidant Status (TOS) kit and Total Antioxidant Status (TAS) kit. The statistics of results were done by SPSS version 21. Results: 58 patients were included consisting of β thalassemia intermedia (n=16) and β thalassemia major (n=42). The total oxidant capacity was found higher in patients than control group without significant differences. Beside this, the antioxidant capacity of patients was significantly increased (2.75 mmol/l vs 1.94 mmol/l; p=0.001). Within patients group, there was no significant differences in terms of TAC while the TOC level was high in NTDT (2.99 mmol/l vs 1.88 mmol/l; p=0.08). There was no significant relationship between TOC and sex, age (<18 vs >18 years), ferritin and splenectomy status, as the same for TAC. Conclusions: The oxidative damage in patients with β-thalassemia can trigger the morbidity. The measurement of TOC and TAC status stands a useful, rapid, and simple method to evaluate the complex oxidative mechanism of disease. There are still controversial results about antioxidant status in thalassemia patients. The irregular consume of supportive treatment such as zinc, vitamin C, vitamin E and herbal medicine may affect the TOC and TAC status. The results of this study can guide us to use the antioxidants to decrease the oxidative stress. Figure 1. Figure 1. Disclosures No relevant conflicts of interest to declare.

Role of Iron Chelators, Hydroxyurea, and Splenectomy on Serum Total Antioxidant Capacity in β-Thalassemia

“…There was no significant relationship between TAC and splenectomy status. Same result was reported by Karakas et al [16]. No correlation existed between TAC and age, sex in thalassemia patients, or controls.…”

“…No correlation existed between TAC and age, sex in thalassemia patients, or controls. Karakas et al [16] reported the same results. Our results indicate that there was a negative non-significant correlation between TAC and ferritin.…”

“…Our results indicate that there was a negative non-significant correlation between TAC and ferritin. Different studies showed the same result [10,16].…”

“…Bazvand et al reported a significant increase in antioxidant status in Iranian βT patients when compared to normal controls [9]. Besides this, Karakas et al reported that TAC was significantly increased in β-TM and β-TI [16]. It must be pointed out that another study showed decreased levels of TAC in Italian and Greek βT patients [5].…”

“…Furthermore, genetic mutations in different population may result in different responses to oxidative stress [11]. A probable mechanism to explain the increased antioxidant status in patients with βT is the compensating antioxidant response due to excessive oxidative stress [16]. Endogenous antioxidants such as ferritin, bilirubin, and uric acid can result in increased level of TAC in patients with β-TM [9].…”