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Hemoglobin (Hb) and iron are prooxidants in nature and sources of free radicals in the biological system of all Hb phenotypes. Recent evidence linked abnormal hemoglobin S and C (HbSC) in sickle cell disease (SCD) to various complications in multiple oxidative processes. However, similar studies in relation to abnormal Hb traits are sparse. Besides, reports on activities of antioxidant enzymes and iron status in SCDs are still contradictory. This study assessed the interplay between lipid peroxidation and antioxidant defense capacity in various Hb variants. We enrolled 193 participants with different Hb phenotypes. They were consecutive patients with sickle cell anemia (HbSS, n = 32) and hemoglobin SC (HbSC) disease (n = 28) regularly followed up in a steady state. Other participants were subjects with abnormal Hb traits (HbAS, n = 50; HbAC, n = 33) and normal controls (HbAA, n = 50). The hematocrit (Hct) level, hemoglobin (Hb) concentration, iron status, and biochemical parameters including malondialdehyde (MDA), total antioxidant status (TAS), superoxide dismutase (SOD), and glutathione peroxidase (GPx) enzymes were investigated simultaneously. The MDA and SOD levels were significantly higher (P < 0.05) in Hb variants in order of HbSS>HbSC>HbAC>HbAS when compared with controls. Conversely, GPx and TAS levels showed significant reductions (P < 0.05). Similarly, Hct, Hb, and iron concentrations showed significant reductions (P < 0.05) sequentially following HbAC > HbAS > HbSC > HbSS compared with controls. The results suggest that both SCDs and the carriers were relatively more vulnerable to systemic oxidative stress against normal phenotype, and may be owing to ineffective antioxidant mechanisms needed for keeping spontaneous generations of free radicals in control without necessarily iron-mediated., (© 2019 The Authors. The Kaohsiung Journal of Medical Sciences published by John Wiley & Sons Australia on behalf of Kaohsiung Medical University.)

Background: The high prevalence of sickle cell disorders and the mild deletional alpha-thalassaemia among Nigerians is well known, but beta-thalassaemia is believed to be almost nonexistent. Beta thalassaemia trait (BTT) was screened for in patients with unexplained recurrent haemolytic anaemia and healthy individuals., Methods: beta-thalassaemia trait (BTT) was screened for using MCH and HbA2 of 27 pg and 3.5% respectively as cut off in 151 Nigerians which included 29 patients and 122 apparently healthy individuals. The subjects were categorized into four, Group I (high HbA2, low MCH), Group II (low HbA2 and MCH), Group III (high HbA2 and high/normal MCH) and Group IV (normal HbA2 and MCH)., Results: Group I are possible carriers of BTT while group IV are least likely to carry either alpha or beta thalassaemia genes. There were 36 (26%), 39 (28%), 27 (19%) and 38 (27%) in groups I-IV respectively. The mean MCH, MCV, haematocrit and HbA2 for the study population were 26 +/-2.8, 81 +/- 7.9, 37.5 +/- 6.8 and 3.4 +/- 1.7 respectively. The mean MCV and haematocrit were significantly lower for group I compared to group IV (76.9 Vs 86.6, p = 0.00) and (36.5Vs39.7, p = 0.03) respectively. Group II had significantly lower MCV and haematocrit than group IV (75.4 (p = 0.00) and 36.4 (p = 0.01) respectively. There was a positive correlation between the MCH and MCV with the haematocrit (p = 0.004, p = 0.001 respectively) but HbA2 showed a stronger negative correlation with the haematocrit (p < 0.0001)., Conclusion: This does not only show the presence of BTT, but a higher prevalence than previously thought, mutations responsible for it should therefore be characterized.