Antioxidant deficit and enhanced susceptibility to oxidative damage in individuals with different forms of α‐thalassaemia

Abstract

Summary α‐Thalassaemia is a common red cell disorder in Taiwan, affecting 6–8% of Taiwanese. Previous studies have shown that reactive oxygen species are generated in increased amounts in thalassaemic red cells. This implies the possible alteration of redox status in thalassaemic patients, which may adversely affect their health. In the present study, the redox status of patients with α‐thalassaemia trait and haemoglobin H (Hb H) disease was investigated. Lipid peroxidation, as measured by the level of plasma thiobarbituric acid reactive substances (TBARS), was increased in α‐thalassaemic patients, with the highest level of TBARS in Hb H disease patient. The plasma levels of vitamin A, C, and E were significantly lower in α‐thalassaemic patients than in controls. The overall antioxidant capacity in plasma was inversely correlated with the severity of α‐globin gene defect: the more severe the form of α‐thalassaemia, the lower the overall antioxidant capacity in plasma. Erythrocytes isolated from α‐thalassaemia patients had lower levels of vitamin E, glutathione, catalase and superoxide dismutase. In addition, these α‐thalassaemic red cells were more susceptible to hydrogen peroxide‐induced lipid peroxidation and decrease in deformability. All these data suggest that the α‐thalassaemic patients suffer from increased oxidative stress and antioxidant deficit, which may complicate the pathophysiology of α‐thalassaemia.

Ischemia-modified albumin as a marker of vascular dysfunction and subclinical atherosclerosis in β-thalassemia major

“…MDA levels were also elevated in β-TM patients (median [IQR], 30 nmol/ ml) with a range of 10-112 nmol/ml compared with the control group (median [IQR], 10 [7][8][9][10][11][12][13][14][15] nmol/ml; range 5-18 nmol/ml); p < 0.001 (Table 1 and Figure 1).…”

“…Liver lipid peroxidation also increases leakage of ferritin into the circulation. Levels of MDA have been reported to be correlated with iron concentrations in the liver as well as serum ferritin of thalassemia patients [5,7,8].…”

Epistasis between the haptoglobin common variant and α+thalassemia influences risk of severe malaria in Kenyan children

“…A number of mechanisms for an epistatic interaction seem plausible, a few of which are summarized here. Individuals with a 1 thalassemia are under increased oxidative stress, 41 a fact that likely relates to an intraerythrocytic excess of unmatched b chains and reactive free thiols.…”

Oxidative Stress, Hepcidin and Nesfatin-I Status in Childhood Iron and Vitamin B12 Deficiency Anemias

“…16 In anemias, due to Thalassemia and G6PD enzyme deficiency, it has been shown that oxidative stress increases and antioxidant capacity is reduced. 17 In contrast, Acharya et al reported an increase in the levels of antioxidant enzymes in patients with iron deficiency anemia, and they suggested that this was due to overcompensation against the induced oxidative stress. 18 Al-Maskari et al reported that hyperhomocysteinemia with folate and vitamin B12 deficiency causes oxidative stress and there is also a parallel decline in the total antioxidant capacity.…”