Figure 3.

CoQ₀ promotes cytoprotective autophagy as a survival mechanism in SKOV-3 cells. (A) Cells were treated with various concentrations of CoQ₀ (0–30 µM) for 24 h and then conversion of LC3-I to LC3-II was determined by Western blot. Relative changes in the intensities of protein bands were quantified by commercially available quantitative software. (B) CoQ₀ induces AVOs formation. Cells were treated with CoQ₀ (0–30 µM) for 24 h and stained with AO. Formation of AVOs, represented by red fluorescence intensity (in lysosomes) was visualized under a red filter fluorescence microscope (100 × magnification). Number of AO stained cells was presented as histogram, control being as 1.0 fold. (C) CoQ₀ promotes conversion of GFP-LC3. Cells were transfected with GFP-LC3 expression vector for 24 h, and then treated with CoQ₀ (0–30 µM) for 24 h. GFP-LC3 dots in cells were observed under a confocal microscope (200 × magnification). Conversions of GFP-LC3 and endogenous LC3 were determined by Western blot. (D) Cells were treated with autophagy inhibitors (2 mM 3-MA or 10 μM CQ) for 1 h followed by CoQ₀ (0–30 µM) for 24 h, and viability was assayed by MTT assay. Results expressed as mean ± SD of three independent assays (n = 3). Significant at **p < 0.01; ***p < 0.001 compared with untreated control, and significant at ^## p < 0.01; ^### p < 0.001 compared with CoQ₀ alone treated cells.