Figure 2.

Effect of tectorigenin on catalase. (A) Catalase activity is expressed as the average number of enzyme units per milligram of protein ± SE. *Significantly different from control cells (P < 0.05). (B) Cell lysates were electrophoresed and expression of catalase was detected using a specific antibody. (C) After treatment with 3-amino-1,2,4-triazole (ATZ), tectorigenin, and/or H₂O₂, cell viability was determined by the MTT assay. *Significantly different from H₂O₂-treated cells (P < 0.05). **Significantly different from tectorigenin plus H₂O₂-treated cells (P < 0.05).