Fig. 5.

Effect of N-acetyl-l-cysteine (NAC) on direct DNA damage and micronucleus (MN) induction in BEAS-2B cells exposed to β-damascone (β-Dam) or mitomycin C (MMC). The fold changes for γH2AX foci per cell as a direct DNA damage marker (a) and frequency of micronucleated cells (% MN frequency) (b) after 24 h of exposure to β-Dam or MMC were calculated from the solvent control value without NAC co-treatment. The solid and dotted lines represent the values obtained with or without NAC co-treatment, respectively. The closed and open symbols or bars represent the values obtained at concentrations causing more than and less than 50% relative cell number, respectively. Each result represents the mean and standard error of the mean for three independent experiments. #Significantly different from the solvent control group (P < 0.05, Dunnett's test). *Significantly different from the solvent control group (P < 0.05, Welch's t-test)