M2 monocyte polarization in dialyzed patients is associated with increased levels of M-CSF and myeloperoxidase-associated oxidative stress: preliminary results

Abstract

AbstractCardiovascular diseases represent a major issue in terms of morbidity and mortality for dialysis patients. This morbidity is due to the accelerated atherosclerosis observed in these patients. Atherosclerosis is a chronic inflammatory disease characterized by key players such as monocytes, macrophages or oxidized LDLs. Monocytes-macrophages are classified into subsets of polarized cells, with M1 and M2 macrophages considered respectively as pro- and anti-inflammatory.The monocyte subsets and phenotypes were analyzed by flow cytometry. These data was completed by the quantification of plasma M-CSF, IL-8, CRP, Mox-LDLs, Apo-B and Apo-AI, chloro-tyrosine and homocitrulline concentrations.The statistical differences and associations between two continuous variables were assessed using the Mann-Whitney U test and Spearman’s correlation coefficient, respectively.Hemodialyzed patients showed a significant increase in the concentrations of CRP, M-CSF and IL-8 (inflammation biomarkers) as well as of chloro-tyrosine and homocitrulline (myeloperoxidase-associated oxidative stress biomarkers). Moreover we observed a higher percentage of M2 monocytes in the plasma of hemodialysis patients, as compared to the controls.Our data suggests that an oxidative stress and an inflammatory environment, amplified in hemodialysis patients, seems to favor an increase in the concentration of circulating M-CSF, therefore leading to an increase of M2 polarization among circulating monocytes.Short summaryOur data suggests that an oxidative stress and an inflammatory environment, amplified in hemodialysis patients, seems to favor an increase in the concentration of circulating M-CSF, associated with an increase of circulating M2 polarized monocytes.