Figure 4.

Western blotting was performed to assess the effects of quercetin on the expression of Bcl-2, Bax, caspase-3, cleaved caspase-3, and cleaved PARP in NaIO₃-treated ARPE-19 cells. ARPE-19 cells were pretreated with different concentrations of quercetin (1.25, 2.5, and 5 μM) for 1.5 h and then treated with NaIO₃ (6 mM) for 24 h. Data were normalized to β-tubulin. Values represent the mean ± SD (n = 3). Data bars without letters in common (a–d) indicate a significant difference (p < 0.05).