miR302a and 122 are deregulated in small extracellular vesicles from ARPE-19 cells cultured with H2O2.

Age related macular degeneration (AMD) is a common retina-related disease leading to blindness. Little is known on the origin of the disease, but it is well documented that oxidative stress generated in the retinal pigment epithelium and choroid neovascularization are closely involved. The study of circulating miRNAs is opening new possibilities in terms of diagnosis and therapeutics. miRNAs can travel associated to lipoproteins or inside small Extracellular Vesicles (sEVs). A number of reports indicate a significant deregulation of circulating miRNAs in AMD and experimental approaches, but it is unclear whether sEVs present a significant miRNA cargo. The present work studies miRNA expression changes in sEVs released from ARPE-19 cells under oxidative conditions (i.e. hydrogen peroxide, H2O2). H2O2 increased sEVs release from ARPE-19 cells. Moreover, 218 miRNAs could be detected in control and H2O2 induced-sEVs. Interestingly, only two of them (hsa-miR-302a and hsa-miR-122) were significantly under-expressed in H2O2-induced sEVs. Results herein suggest that the down regulation of miRNAs 302a and 122 might be related with previous studies showing sEVs-induced neovascularization after oxidative challenge in ARPE-19 cells.