Expression Profiling of Exosomal miRNAs Derived from the Aqueous Humor of Myopia Patients

Myopia is the most common refractive disorder in Eastern Asia. The development of myopia is associated with the cooperation of various ocular tissues. Exosomes in the aqueous humor (AH) have been implicated to modulate intracellular communications by transferring exosomal miRNAs and proteins between cells. These exosomal miRNAs and proteins are likely involved in the pathogenesis of various eye diseases. In this study, we aimed to explore human exosomal miRNA profiles and their roles in myopia development. AH samples were collected from 16 patients (8 myopia and 8 control) undergoing routine cataract surgeries. Exosomes were isolated from AH of each individual using the ExoQuick solution. The numbers and sizes of exosomes were not significantly different between the myopia and control groups. The individual exosomes of the same group were pooled to purify RNA. Unexpectedly, the myopia group contained 2.78-fold total RNA amount than that in the control group. Thereafter, miRNA profiles were analyzed using the OpenArray system. We thus found 15 myopia-specific miRNAs and four myopia-absent miRNAs. By using bioinformatics analysis, we identified six well-known myopia-associated genes that are potential targets of five myopia-specific miRNAs (has-miR-582-3p, has-miR-17-5p, has-miR-885-3p, has-miR-19b-3p, and has-miR-450b-5p). These genes are cholinergic receptor muscarinic 2 (CHRM2), cyclic nucleotide-gated channel beta 3 (CNGB3), vascular endothelial growth factor A (VEGFA), adenosine A2a receptor (ADORA2A), insulin-like growth factor 1 (IGF1), and lumican (LUM). Moreover, CHRM2 may be a target of myopia-absent miRNA (has-miR-378a-5p). In conclusion, we show the expression profiles of AH-derived exosomal miRNAs and their potential roles in myopia development.