Fig. 4

Autophagy alleviates ER stress for cell survival in blue light-mediated damage of A2E-laden RPEs. a: RPEs were preincubated with 10 nM rapamycin or 5 mM 3-MA for 2 h, then cultured with 25 μM A2E for 2 h and exposed to blue light for 20 min. Cells were collected 12 h later. Western blot was used to measure LC3, CHOP and caspase-12 protein levels. Bars represent the mean ± SD from three independent experiments (n = 3, *p < 0.05). b: The immunofluorescence of LC3 was measured by confocal laser microscopy. In rapamycin pretreated group, LC3 showed an increased punctate distribution. On the contrary, 3-MA attenuated LC3 dots formation (scale bar, 10 μm). The number of autophagosomes was obtained by counting LC3 fluorescent puncta in RPEs from three independent experiments (n = 3, *p < 0.05). c: Cell death in RPEs was measured by TUNEL analysis at 12 h after A2E and blue light treatment (scale bar, 10 μm). The cell death rates are reported as percentage of TUNEL positive cells (n = 3, *p < 0.05)