BMSC-derived exosomes attenuate persistent corneal epithelial injury by affecting retinal neural-like cells

Abstract

Persistent corneal epithelial defect (PED) is a challenge to human which is difficultly cured, normally requiring long-term follow-up. Herein, this study explored the potential role of bone marrow mesenchymal stem cell-derived exosomes (BMSC-exos) in persistent corneal epithelial injury and the underlying mechanism. After characterization of BMSC-exos, RGC-5 cell viability was determined and surface markers of BMSCs were analyzed. Additionally, RT-qPCR and Western blot measured miR-150-5p, Brn3, Islet-1, and PCNA expression. Dual luciferase assays were conducted to evaluate the targeting relationship between long non-coding Ribonucleic Acid (lncRNA) MIAT and miR-150-5p. Presented in ellipsoidal or cup shape, BMSC-exos were positive to BMSC-specific markers CD29 and CD90, and cell surface markers CD9 and CD63 were detected on exosomes. Importantly, treatment with BMSC-exos significantly promoted proliferation of retinal ganglion cells (RGCs) and hindered cell differentiation. Interestingly, down-regulating lncRNA MIAT exerted the same effect as BMSC-exos, increasing cell viability and decreasing the expression of differentiation-related proteins Brn3 and ISL1. Bioinformatics software predicted miR-150-5P as target of lncRNA MIAT, and the relative luciferase activity of miR-150-5P+MIAT-WT co-transfection group was lower. Conclusively, BMSC-exos can improve PED by targeting and regulating miR-150-5p expression through lncRNA MIAT, which can up-regulate PCNA in RGC-5 cells and down-regulate Brn3 and ISL1.