The influence of hydroxyurea on oxidative stress in sickle cell anemia

• Published in: Revista brasileira de hematologia e hemoterapia Vol. 34; no. 6; pp. 421 - 425
• Main Authors: Torres, Lidiane de Souza, da Silva, Danilo Grünig Humberto, Belini Junior, Edis, de Almeida, Eduardo Alves, Lobo, Clarisse Lopes de Castro, Cançado, Rodolfo Delfini, Ruiz, Milton Artur, Bonini-Domingos, Claudia Regina
• Format: Journal Article
• Language: English
• Published: Brazil Associação Brasileira de Hematologia e Hemoterapia 2012; Associação Brasileira de Hematologia e Hemoterapia e Terapia Celular; Elsevier
• Subjects: Anemia, sickle cell; HEMATOLOGY; Hemoglobinopathies; Hydroxyurea; MEDICINE, RESEARCH & EXPERIMENTAL; Original; Oxidative stress; Oxidative stress; Hydroxyurea; Hemoglobinopathies; Anemia, sickle cell
• ISSN: 1516-8484; 1806-0870; 1806-0870
• DOI: 10.5581/1516-8484.20120106

The oxidative stress in 20 sickle cell anemia patients taking hydroxyurea and 13 sickle cell anemia patients who did not take hydroxyurea was compared with a control group of 96 individuals without any hemoglobinopathy.
Oxidative stress was assessed by thiobarbituric acid reactive species production, the Trolox-equivalent antioxidant capacity and plasma glutathione levels.
Thiobarbituric acid reactive species values were higher in patients without specific medication, followed by patients taking hydroxyurea and the Control Group (p < 0.0001). The antioxidant capacity was higher in patients taking hydroxyurea and lower in the Control Group (p = 0.0002 for Trolox-equivalent antioxidant capacity and p < 0.0292 for plasma glutathione). Thiobarbituric acid reactive species levels were correlated with higher hemoglobin S levels (r = 0.55; p = 0.0040) and lower hemoglobin F concentrations(r = -0.52; p = 0.0067). On the other hand, plasma glutathione levels were negatively correlated with hemoglobin S levels (r = -0.49; p = 0.0111) and positively associated with hemoglobin F values (r = 0.56; p = 0.0031).
Sickle cell anemia patients have high oxidative stress and, conversely, increased antioxidant activity. The increase in hemoglobin F levels provided by hydroxyurea and its antioxidant action may explain the reduction in lipid peroxidation and increased antioxidant defenses in these individuals.