[The antioxidant therapy modulates intracellular lymphokine expression in children on dialysis]

Oxidative stress (SOX) is believed to be responsible for functional disabilities of lymphocytes in end-stage renal disease (ESRD). Therefore, we investigated the effect of antioxidant therapy with vitamin E and N-acetylcysteine (NAC) on SOX and cytokine synthesis in T cells in dialyzed children. Eighteen children (aged 2-20, mean 10.9 yr) treated with hemodialysis (n=5) and peritoneal dialysis (n=13) were enrolled into the study. Vitamin E and NAC were given orally for six months. Throughout the study, intracellular lymphokines [interleukin (IL)-2, interferon (IFN)-gamma, IL-4, IL-6] and SOX in T cells were measured by means of flow cytometry. In dialyzed children, mean fluorescence intensity (MFI), which reflected intracellular SOX, was significantly higher than in the controls in both CD3+ and CD3+CD4+ cells (p<0.05). We also found a cytokine dysregulation with a trend toward a predominant T helper (Th)-1 response compared to the controls. After 6 months of treatment with antioxidants, a significant reduction in MFI was noted compared to baseline values in CD3+ and CD3+CD4- cells (p<0.001). Interestingly, the therapy led to a decrease in IFN-gamma as well as an increase in IL-4 and IL-6 production. In addition, a gradual decline in IFN-gamma/IL-4 ratio in Th cells was noted.

Vitamin E and NAC used in combination are effective in reducing the intracellular SOX, and besides their action on cellular redox state, they modulate the cytokine profile in children on dialysis.