Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
J Cell Biochem. 2019 Dec;120(12):19635-19646. doi: 10.1002/jcb.29270. Epub 2019 Jul 24.
Age-related cataract is one of the prior causes of blindness and the incidence rates of cataract are even rising. Oxidative stress plays an important role in the pathogenesis of cataracts. Under oxidative stress, lens epithelial cell (LEC cell) apoptosis is activated, which might lead to the opacity of the lens and accelerate the progression of cataract development. Meanwhile, autophagy is also active to face oxidative stress. miRNAs have been reported to involve cataract. However, the underlying mechanism is not clear. The present study aimed to investigate the regulatory effect of miR23b-3p on apoptosis and autophagy in LEC cells under oxidative stress. The expression levels of miR-23b-3p were examined in age-related cataract tissues and LEC cells treated with hydrogen peroxide, showing that miR23b-3p expression levels were upregulated. Knockdown of miR23b-3p expression in LEC cells brought about apoptosis significantly decreased while autophagy significantly increased during hydrogen peroxide. We predicted microRNA miRNA-23b-3p might participate in regulating silent information regulator 1 (SIRT1) by bioinformatics database of TargetScan. Luciferase reporter assays confirmed that miRNA-23b-p could suppress SIRT1 expression by binding its 3'UTR. In addition, overexpression or knockdown of miR-23b-3p could decrease or increase SIRT1 expression, which indicated that Mir-23b-3p could suppress SIRT1 expression. In addition, enhanced SIRT1 could attenuate the regulation of cell apoptosis and autophagy induced by overexpression of miR-23b-3p. Taken together, our findings revealed that miR-23b-3p regulated apoptosis and autophagy via suppressing SIRT1 in LEC cell under oxidative stress, which could provide new ideas for clinical treatment of cataract.
年龄相关性白内障是失明的首要原因之一,白内障的发病率甚至在上升。氧化应激在白内障的发病机制中起重要作用。在氧化应激下,晶状体上皮细胞 (LEC 细胞) 凋亡被激活,这可能导致晶状体混浊,并加速白内障的发展。同时,自噬也会积极应对氧化应激。已有研究报道 miRNA 参与白内障的发生。然而,其潜在的机制尚不清楚。本研究旨在探讨 miR23b-3p 在氧化应激下对 LEC 细胞凋亡和自噬的调控作用。检测了年龄相关性白内障组织和过氧化氢处理的 LEC 细胞中 miR-23b-3p 的表达水平,结果显示 miR23b-3p 表达水平上调。在过氧化氢处理的 LEC 细胞中,下调 miR23b-3p 的表达可显著减少细胞凋亡,同时显著增加自噬。通过生物信息学数据库 TargetScan 预测 miR-23b-3p 可能参与调节沉默信息调节因子 1 (SIRT1)。荧光素酶报告基因检测证实 miR-23b-3p 可通过结合其 3'UTR 抑制 SIRT1 表达。此外,miR-23b-3p 的过表达或下调可降低或增加 SIRT1 的表达,表明 Mir-23b-3p 可抑制 SIRT1 的表达。此外,增强 SIRT1 可减弱 miR-23b-3p 过表达诱导的细胞凋亡和自噬的调节作用。综上所述,本研究结果表明,miR-23b-3p 通过抑制氧化应激下 LEC 细胞中的 SIRT1 调节细胞凋亡和自噬,为白内障的临床治疗提供了新的思路。