Protective Effect of Melatonin against Oxidative Stress-Induced Apoptosis and Enhanced Autophagy in Human Retinal Pigment Epithelium Cells

Figure 5

Melatonin increases autophagy in RPE cells. ARPE-19 cells were pretreated with melatonin (50 and 100 μM) for 48 h and exposed to 300 μM H₂O₂ for 24 h. Expression levels of proteins are presented in (a–h). Expression levels of LC3 (a, b). LC3 was determined using ICC in ARPE-19 cells (magnification, ×40) (c). Expression levels of Beclin-1 (d). Expression levels of p62 (e). p62 was determined using ICC in ARPE-19 cells (magnification, ×40) (f). Expression levels of mTOR and p-mTOR (Ser2448) (g). Expression levels of ULK1 and p-ULK1 (Ser757) (h). Protein expression was calculated from densitometry absorbance values after correction for GAPDH expression to obtain equal loading. Values are the mean ± SD. versus the control group and versus H₂O₂-treated cells (scale bars are 100 μm).

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