B-ext, L-ext, their active components, and NAC inhibited blue LED light-induced 661 W cell death. (A) Representative fluorescence microscopy images of Hoechst 33342 (blue color) and propidium iodide (PI) (red color) staining after 12 h of blue LED light exposure. Scale bar, 50 μm. Inhibitory effects of B-ext (B), L-ext (C), NAC (D), delphinidin, cyanidin, malvidin (E), resveratrol, and procyanidin B2 (F) on blue LED light-induced retinal cell death in 661 W cells. The number of cells exhibiting PI fluorescence was counted and expressed as a percentage of Hoechst 33342-positive cells. Cells were treated with B-ext, L-ext, NAC, delphinidin, cyanidin, malvidin, trans- resveratrol, and procyanidin B2 for 1 h, and then exposed to 2500 lx of blue LED light for 6 h. Data are means ± SEM (n = 6). C, control; V, vehicle; B-ext, bilberry extract; L-ext, lingonberry extract; NAC, N-acetyl-l-cysteine; Dp, delphinidin; Cy, cyanidin; Mv, malvidin; Res, trans-resveratrol; PC, procyanidin B2. ##
p < 0.01 vs. control; *p < 0.05, **p < 0.01 vs. the vehicle-treated group (Dunnett’s multiple comparison test or Student’s t-test).