Beneficial in vitro effect of N-acetyl-cysteine on oxidative stress and apoptosis.

Chronic renal failure (CRF) is usually accompanied by abnormalities of both humoral and cellular immune response. The aim of the study was to investigate the influence of N-acetyl-cysteine (NAC) on intracellular oxidative stress and apoptosis rate of T lymphocytes in children with CRF. Twenty-two children (aged 4-16, mean 7.4) with CRF treated with dialysis were enrolled in the study. Intracellular reactive oxygen species (ROS) production was quantified by mean rhodamine 123 (RHO) fluorescence intensity with flow cytometry. Annexin V FITC was used for identifying apoptotic cells. Mean fluorescence intensity (MFI), which reflected intracellular oxidative stress in T lymphocytes, was increased in patients with CRF compared with the controls (CD3+: 31.58+/-11.58 vs 22.55+/-4.97, p = 0.043; CD3+CD4+: 32.50+/-8.59 vs 27.75+/-12.76, NS; CD3+CD8+: 32.10+/-11.85 vs 20.77+/- 4.89, p =0.012). Apoptotic T lymphocytes occurred more frequently in patients with CRF treated with hemodialysis (HD) (11.36+/-6.96%) than in the controls (6.14%+/-3.36%; p = 0.025). After 24 h incubation with NAC MFI and apoptosis rate decreased significantly in all subpopulations of lymphocytes. NAC, as a strong antioxidant, has a favorable effect on intracellular oxidative stress and apoptosis rate of T lymphocytes in patients with CRF. A decreased apoptosis rate may have positive effect on functional abnormalities of T cells already found in patients with CRF.