Keywords
High glucose
Retinal pigment epithelial cell
Autophagy
Cell culture
Submitted : 2023-08-26
Accepted : 2023-09-10
Published : 2023-09-25
Abstract
Objective: To study the effects of Lycium barbarum polysaccharide (LBP) on the proliferation, apoptosis, and
autophagy of retinal pigment epithelial (RPE) cells cultured under high-glucose conditions. Methods: The ARPE-19 cell line was randomly divided into a control group (normally cultured in Dulbecco’s Modified Eagle Medium/Nutrient Mixture F-12 [DMEM/F-12] medium), a high-glucose group (HG; 50 mmol/L glucose added to DMEM/F-12 medium), and a HG+LBP group (incubated in DMEM/F-12 medium containing 1 mg/mL LBP for 24 h, and then treated with 50 mmol/L glucose for 24 h). Following Ad-mCherry-GFP-LC3B infection, cell proliferation, apoptosis, mammalian target of rapamycin (mTOR) expression, and autophagic flux were determined by Cell Counting Kit-8 (CCK-8), AnnexinV-APC/7-AAD Apoptosis Detection Kit, Western blot, and laser confocal microscopy, respectively. Results: The proliferation rate of ARPE-19 cells in the HG group was significantly lower than that in the control group (P < 0.05), while the proliferation rate of ARPE-19 cells in the HG+LBP group was significantly higher than that in the HG group (P < 0.05). The apoptosis rate of ARPE-19 cells in the HG group was significantly higher than that in the control group (P < 0.05), while the apoptosis rate of ARPE-19 cells in the HG+LBP group was significantly lower than that in the HG group (P < 0.05). The relative expression of phosphorylated mTOR (p-mTOR) of ARPE-19 cells in the HG group was significantly lower than that in the control group (P < 0.05), with enhanced autophagic flux; when compared with the HG group, the HG+LBP group had significantly higher expression of p-mTOR (P < 0.05), with diminished autophagic flux. Conclusion: LBP has a protective effect on RPE cells with high glucose-induced injury, and its mechanism may be related to LBP inhibition of high glucose-induced abnormal autophagy.
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