Fig. 3From: Oxidative stress mediated by gyrophoric acid from the lichen Umbilicaria hirsuta affected apoptosis and stress/survival pathways in HeLa cellsa Effect of GA alone or after NAC pre-treatment on caspase-3 activity. b Effect of GA alone or after NAC pre-treatment on PARP cleavage. Data represents mean ± SD from 3 independent experiments. Significance: * P < 0.05, ** P < 0.01, *** P < 0.001 versus untreated cells (control); + P < 0.05, ++ P < 0.01, versus GABack to article page