Antioxidants attenuated the effects of NADH treatment on the survival of C6 glioma cells. The cells were pre-treated with N-acetyl cysteine (NAC) (A) or Trolox (B) for 30 min, followed by co-treatment with 100 or 1000 μM NADH for 24 hrs. The percentage of cell survival was assessed by LDH assay. N = 16. Data were pooled from 4 independent experiments. *, p < 0.05, **, p < 0.01, ***, p < 0.001.