Inhibition of UVA-induced GSH depletion (A and B) and GST inactivation (C and D) by AVS073 and GA. GSH level and GST activity were determined by measurement of fluorescence of the GSH-OPA adduct and absorbance of the GSH-CDNB, respectively. The GSH content and GST activity related to the protein concentrations were expressed as a percentage of control (100%, untreated cells without UV irradiation). Values are expressed as mean±SEM. The statistical significance of differences between the control and UVA-irradiated cells was determined by Student’s t test and between UVA-irradiated and AVS073 extracts- or GA-treated cells by one-way ANOVA followed by Tukey’s post hoc test. *p < 0.05; **p < 0.01; ***p < 0.001 compared with AVS073- or GA-treated cells without UV irradiation.