Influence of βS-globin haplotypes hydroxyurea on tumor necrosis factor-alpha levels in sickle cell anemia

ABSTRACTBackgroundSickle cell anemia is a chronic inflammatory disease characterized by an increased production of proinflammatory cytokines including tumor necrosis factor-alpha. Hydroxyurea, by decreasing the polymerization of hemoglobin, reduces inflammatory states. The effect of the genetic polymorphisms of sickle cell patients on tumor necrosis factor-alpha levels remains unknown.ObjectiveThe aim of this study was to investigate the association of tumor necrosis factor-alpha levels with β-globin haplotypes and the use of hydroxyurea.MethodsA cross-sectional study was performed of 67 patients with sickle cell anemia diagnosed at steady-state in a referral hospital in Fortaleza, Ceará, Brazil. A group of 26 healthy individuals was used as control. βS haplotype analysis was performed by restriction fragment length polymorphism-polymerase chain reaction. The tumor necrosis factor- alpha levels were measured by the enzyme-linked immunosorbent assay test. Laboratory data (complete blood count and fetal hemoglobin) and information regarding the use of hydroxyurea were obtained from medical records. Statistical analysis was performed using R software with the Kruskal-Wallis and Mann–Whitney tests. Statistical significance was established for p-values<0.05 for all analyses.ResultsThe mean age of the participants was 35.48years. Patients with sickle cell anemia had significantly higher tumor necrosis factor-alpha levels than controls (p-values