Circular RNA HIPK3 regulates human lens epithelial cell dysfunction by targeting the miR-221–3p/PI3K/AKT pathway in age-related cataract. (September 2020)

• Record Type: Journal Article
• Authors: Cui, Gangfeng; Wang, Ledan; Huang, Wenjuan
• Is Part Of: Experimental eye research. Volume 198(2020)
• Publication Date: 2020-09
• Subjects: circHIPK3 -- miR-221–3p -- PI3K/AKT pathway -- Cataract; Ophthalmology -- Periodicals; Eye -- Periodicals; Œil -- Périodiques; Ophthalmology; Periodicals; Electronic journals; 612.8405
• DOI: 10.1016/j.exer.2020.108128
• Languages: English
• ISSNs: 0014-4835

Abstract

Abstract: Circular RNA Homeodomain Interacting Protein Kinase 3 (circHIPK3) was found to involve in the pathogenesis of age-related cataract (ARC). Here, we further disclosed the related target genes and molecular mechanism of circHIPK3 in the ARC progression. The expression of circHIPK3, microRNA (miR)-221–3p was detected using the quantitative real-time polymerase chain reaction. Human lens epithelial cell (HLEC) proliferation and apoptosis were measured by 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di-phenytetrazoliumromide (MTT) assay and flow cytometry, respectively. Western blot was used to detect the levels of apoptosis-related proteins, and phosphoinositide 3-kinase (PI3K)/p-protein kinase B (AKT) pathway-related proteins. Levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) were measured by kits. The interaction between miR-221–3p and circHIPK3 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay. CircHIPK3 was down-regulated while miR-221–3p was up-regulated in human lens epithelium samples of ARC patients. CircHIPK3 up-regulation or miR-221–3p down-regulation mediated the promotion of proliferation, inhibition of apoptosis, decrease of MDA level as well as increase of GSH-PX level in HLECs. MiR-221–3p was a target of circHIPK3, and miR-221–3p overexpression reversed the protective action of circHIPK in HLEC functions. In addition, circHIPK3 activated PI3K/AKT pathway via regulating miR-221–3p, and silencing miR-221–3p protected HLECs from dysfunction by activating PI3K/AKT pathway. We demonstrated that circHIPK3 protected HLECs from dysfunction by regulating miR-221–3p/PI3K/AKT pathway, indicating a new insight into the pathogenesis of ARC and providing a potential therapeutic target for ARC. Highlights: CircHIPK3 is down-regulated while miR-221–3p is up-regulated in human lens epithelium samples of ARC patients. CircHIPK3 protects HLECs from dysfunction. MiR-221–3p aggravates the damage of HLECs. MiR-221–3p is a target of circHIPK3 and regulates the activation of PI3K/AKT pathway. CircHIPK3/miR-221–3p/PI3K/AKT pathway involves in the modulation of HLEC dysfunction.