The role of anaemia in oxidative and genotoxic damage in transfused β-thalassaemic patients.

Objectives: Redox imbalance and genotoxic damage are commonly observed in β thalassaemic patients. The aim of this study was to assess the role of anaemia in oxidative and genotoxic damage in regularly transfused thalassaemic patients, undergoing iron chelation therapy.

Methods: We studied the relationships of haematological, biochemical and clinical parameters with oxidative (reactive oxygen species and 8-oxo-7,8-dihydro-2'-deoxyguanosine) and genotoxic biomarkers (Comet assay and cytokinesis-block micronucleus test) in blood samples from 105 patients. To reduce the early effect of redox-active iron, samples were collected when pharmacokinetics of the iron chelators ensured their maximum effectiveness. The transfusion regimen, cardiac and hepatic magnetic resonance imaging T2* were evaluated to characterize the patient cohort. Labile plasma iron (LPI) was also assayed.

Results: Haemoglobin level had a significant effect on ROS, %DNA in the tail and micronuclei-micronucleated cell frequency (p < 0.05). Higher Hb values reduced redox imbalance. LPI, detectable in 50.5% of patients, was related to the number of apoptotic and necrotic lymphocytes (p = 0.03), demonstrating the cytotoxic effect of iron.

Discussion: The results highlight that an adequate transfusion regimen is essential to limit oxidative and genotoxic damage in β-thalassemic patients undergoing chelation therapy.

Conclusion: Owing to the higher risk of cancer in the thalassaemic cohorts, specific genotoxicity/oxidative biomarkers should be monitored in order to ameliorate and formulate more personalized disease management.