Fig 1. Protection of H₂O₂-treated C6 cells by 4-HBA.

(A-B) C6 cells were treated with H₂O₂ (100 μM) for 1 hr in the presence or absence of 4-HBA (25, 50, 100, or 250 μM) (A), or pre-treated with 4-HBA (25, 50, 100, or 250 μM) for 3 hrs and then treated with H₂O₂ (100 μM) for 1 hr (B). (C) C6 cells were pre-treated with 4-HBA (100 μM) for 3, 6, or 9 hrs and then treated with H₂O₂ (100 μM) for 1 hr. In all experiments, MTT assays were carried out 24 hrs after H₂O₂ treatment. Changes in cell survival are presented as means±SEMs (n = 3). **p<0.01 versus untreated controls, ^#p<0.05 and ^##p<0.01 between indicated groups.