JCNRJournal of Clinical and Nursing Research2208-36852208-3693Bio-Byword Scientific Publishing Pty. Ltd.10.26689/jcnr.v7i5.4772ArticleProtective Effect and Autophagy Mechanism of Lycium barbarum Polysaccharides on Retinal Pigment Epithelial Cells Under High-Glucose Conditionshttps://artdesignp.com/journal/JCNR/7/5/10.26689/jcnr.v7i5.4772ZhangMin,YaoGuomin,LiRong2023752023-09-22Objective: To study the effects of Lycium barbarum polysaccharide (LBP) on the proliferation, apoptosis, andautophagy 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.

Naylor A, Hopkins A, Hudson N, et al., 2019, Tight Junctions of the Outer Blood Retina Barrier. Int J Mol Sci, 21(1): E211.

Lechner J, O’Leary OE, Stitt AW, 2017, The Pathology Associated with Diabetic Retinopathy. Vision Res, 139: 7–14.

Ponnalagu M, Subramani M, Jayadev C, et al., 2017, Retinal Pigment Epithelium-Secretome: A Diabetic Retinopathy Perspective. Cytokine, 95: 126–135.

Xiao Q, Zhao Y, Xu J, et al., 2019, NFE2/miR-423-5p/TFF1 Axis Regulates High Glucose-Induced Apoptosis in Retinal Pigment Epithelial Cells. BMC Mol Cell Biol, 20(1): 39.

Chai P, Ni H, Zhang H, et al., 2016, The Evolving Functions of Autophagy in Ocular Health: A Double-Edged Sword. Int J Biol Sci, 12(11): 1332–1340.

Rosa MD, Distefano G, Gagliano C, et al., 2016, Autophagy in Diabetic Retinopathy. Curr Neuropharmacol, 14(8): 810–825.

Tian X, Liang T, Liu Y, et al., 2019, Extraction, Structural Characterization, and Biological Functions of Lycium barbarum Polysaccharides: A Review. Biomolecules, 9(9): 389.

Masci A, Carradori S, Casadei MA, et al., 2018, Lycium barbarum Polysaccharides: Extraction, Purification, Structural Characterisation and Evidence About Hypoglycaemic and Hypolipidaemic Effects. A Review. Food Chem, 254: 377–389.

Kwok SS, Bu Y, Lo AC, et al., 2019, A Systematic Review of Potential Therapeutic Use of Lycium barbarum Polysaccharides in Disease. Biomed Res Int, 2019: 4615745.

Yao Q, Yang Y, Lu X, et al., 2018, Lycium barbarum Polysaccharides Improve Retinopathy in Diabetic Sprague-Dawley Rats. Evid Based Complement Alternat Med, 2018: 7943212.

Wang J, Yao Y, Liu X, et al., 2019, Protective Effects of Lycium barbarum Polysaccharides on Blood-Retinal Barrier Via ROCK1 Pathway in Diabetic Rats. Am J Transl Res, 11(10): 6304–6315.

Zhu Y, Zhao Q, Jiang Y, 2021, Lycium barbarum Polysaccharides Attenuates High Glucose-Induced Diabetic Retinal Angiogenesis by Rescuing the Expression of miR-15a-5p in RF/6A Cells. J Ethnopharmacol, 283: 114652.

Yan M, Ma Q, Ma Y, et al., 2021, Effect and Mechanism of Lycium barbarum Polysaccharide on LPS-Induced Inflammatory Response of Human Retinal Pigment Epithelial Cells. International Journal of Ophthalmology, 21(3): 411–416.

Zhang Y, Xi X, Mei Y, et al. High-glucose Induces Retinal Pigment Epithelium Epithelium Mitochondrial Pathways of Apoptosis and Inhibits Mitophagy by Regulating ROS/PINK1/Parkin Signal Pathway. Biomed Pharmacother, 111: 1315–1325.

Cho NH, Shaw JE, Karuranga S, et al., 2018, IDF Diabetes Atlas: Global Estimates of Diabetes Prevalence for 2017 and Projections for 2045. Diabetes Res Clin Pract, 138: 271–281.

Cheung N, Mitchell P, Wong TY, 2010, Diabetic Retinopathy. Lancet, 376(9735): 124–136.

Osaadon P, Fagan XJ, Lifshitz T, et al., 2014, A Review of Anti-VEGF Agents for Proliferative Diabetic Retinopathy. Eye (Lond), 28(5): 510–520.

Happich M, Reitberger U, Breitscheidel L, et al., 2008, The Economic Burden of Diabetic Retinopathy in Germany in 2002. Graefes Arch Clin Exp Ophthalmol, 246(1): 151–159.

Das A, McGuire PG, Monickaraj F, 2016, Novel Pharmacotherapies in Diabetic Retinopathy: Current Status and What’s in the Horizon?. Indian J Ophthalmol, 64(1): 4–13.

Manthey AL, Chiu K, So KF, 2017, Effects of Lycium barbarum on the Visual System. Int Rev Neurobiol, 135: 1–27.

Liu L, Sha XY, Wu YN, et al., 2020, Lycium barbarum Polysaccharides Protects Retinal Ganglion Cells Against Oxidative Stress Injury. Neural Regen Res, 15(8): 1526–1531.

Zoncu R, Efeyan A, Sabatini DM, 2011, mTOR: From Growth Signal Integration to Cancer, Diabetes and Ageing. Nat Rev Mol Cell Biol, 12(1): 21–35.

Fang Y, Tan J, Zhang Q, 2015, Signaling Pathways and Mechanisms of Hypoxia-Induced Autophagy in the Animal Cells. Cell Biol Int, 39(8): 891–898.

Cao Q, 2018, Effect of Lycium barbarum Polysaccharides on Autophagy of Human Retinal Pigment Epithelial Cells Induced by H2O2, thesis, Nanjing University of Traditional Chinese Medicine.