Figure 2.

Ergothioneine protects against apoptosis induced by hydrogen peroxide. (a) Cultured HeLa cells were treated with 1 mM hydrogen peroxide for 16 h after a 24-h pretreatment with 1 mM ET and assayed for cell viability using the MTT Assay. Data are expressed as percentage of viability compared with untreated (designated as U) cells. The ET-treated cells are better protected against H₂O₂ toxicity. Data shown are means ± S.E. of five independent experiments, ***P<0.001 using Student’s t-test. (b) Depletion of the ETT RNA results in increased apoptosis in response to H₂O₂. Cells were transfected with ETT siRNA and 72 h post transfection, treated with or without 1 mM ET for 24 h and then challenged with 0.5 mM H₂O₂ for 16 h. Results are expressed as percentage of viability compared with control, untreated cells. The ETT-depleted cells (black bars) were more susceptible to oxidative stress and showed a marked decrease in viability, P<0.001 using Student’s t-test