Impaired renal function and duration of dialysis therapy are associated with oxidative stress and proatherogenic cytokine levels in patients with end-stage renal disease

Objectives:The present study was undertaken to clarify the role of the impaired renal function and the dialysis therapy on plasma levels of proatherogenic cytokines and Cu/Zn superoxide dismutase (Cu/Zn SOD)—as a marker of oxidative stress (SOX) in uraemia.Design and methods:We have measured the levels of Cu/Zn SOD, monocyte chemoattractant protein-1 (MCP-1) macrophage inflammatory proteins (MIP-1α, MIP-1β) and vascular endothelial growth factor (VEGF) in the plasma of predialysis (CRF) (n = 42), on maintenance hemodialysis (HD) (n = 25) or peritoneal dialysis (PD) (n = 45) patients and in the healthy volunteers (n = 20).Results:The increase in Cu/Zn SOD levels was in PD and HD patients compared to controls (215.56 ± 125.18 and 356.28 ± 122.57 versus 53.53 ± 23.65 ng/ml, respectively). In plasma of the CRF, PD and HD subjects we have also observed the significant increase in the levels of MIP-1β: [31.5 (2–149), 33.0 (1–203) and 76.0 (9–345), respectively]; MCP-1 (616.50 ± 240.15, 943.64 ± 348.99 and 968.50 ± 355.85, respectively) and VEGF (387.93 ± 184.63, 371.56 ± 125.18 and 645.56 ± 136.30, respectively) compared to healthy people. In the predialysis group, creatinine clearance correlated with Cu/Zn SOD and cytokine levels. Moreover, the cytokine levels were also associated with age. In dialysis patients, the correlations were between duration of dialysis treatment and both Cu/Zn SOD and cytokine levels. There was also a direct relationship between Cu/Zn SOD and both MIP-1β and VEGF levels.Conclusions:This study has shown that impaired renal function, age and duration of dialysis treatment are associated with increased oxidative stress and proatherogenic cytokine levels in uremic patients.