Altered levels of cytokines and inflammatory mediators in plasma and leukocytes of sickle cell anemia patients and effects of hydroxyurea therapy

Author(s)

Lanaro, C. ; Franco-Penteado, C. F. ; Albuqueque, D. M. ; Saad, S. T. O. ; Conran, N. ; Costa, F. F. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Fac Ciencias Med, Sch Med, Hematol & Hemotherapy Ctr, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: Journal of Leukocyte Biology; v. 85, n. 2, p. 235-242, Feb. 2009.
• Field of knowledge: Biological Sciences - Pharmacology
• Web of Science Citations: 93

Abstract

Inflammation, cell adhesion to vascular endothelium, and endothelial injury contribute to sickle cell anemia (SCA) vaso-occlusion. Although alterations in inflammatory cytokines and biomarkers have been related, reports have been conflicting, and a conclusive role for these molecules in the disease remains to be established. Furthermore, the effect of hydroxyurea therapy (HU) on the release of inflammatory mediators is not understood. This study aimed to determine plasma levels and leukocyte gene expressions of inflammatory mediators in healthy controls, steady-state SCA patients, and SCA patients on HU therapy. TNF-alpha, IL-8, and PGE(2) levels were significantly higher in the plasma of SCA individuals when compared with control individuals. HU therapy was associated with a significant reversal of augmented TNF-alpha and, interestingly, increased plasma anti-inflammatory IL-10. IFN-gamma, IL-10, cyclooxygenase 2 (COX-2), and inducible NO synthase (iNOS) gene expressions were unaltered in SCA mononuclear cells (MC); however, gene expressions of TNF-alpha, IL-8, and the protective enzyme heme oxygenase-1 (HO-1) were significantly higher. HU therapy was not associated with significantly altered SCA MC inflammatory gene expression, although COX-2 mRNA expression was decreased. In SCA neutrophils, gene expressions of IL-8, IFN-gamma, iNOS, and HO-1 were significantly higher than those of control subjects. Patients on HU demonstrated lower iNOS and higher IL-10 neutrophil gene expressions. Taken together, data suggest that alterations in the gene expressions and productions of a number of pro- and anti-inflammatory mediators are present in SCA and importantly, in those patients on HU therapy. Knowledge of these pathways may contribute to further the understanding of the pathophysiology of this disease. (AU)

• FAPESP's process: 08/57895-1 - National Institute of Blood Technology and Science
• Grantee: Sara Teresinha Olalla Saad
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 07/50853-9 - Investigation of adhesive properties and signaling pathways of neutrophils and platelets and their role in inflammatory diseases
• Grantee: Nicola Amanda Conran Zorzetto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 07/54870-5 - Functional characterization of the protein and its role in cellular proliferation and leukemogenesis
• Grantee: Sara Teresinha Olalla Saad
• Support Opportunities: Regular Research Grants