Identification of Retinopathy of Prematurity Related miRNAs in Hyperoxia-Induced Neonatal Rats by Deep Sequencing

Retinopathy of prematurity (ROP) remains a major problem for many preterm infants. MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression at the posttranscriptional level and have been studied in many diseases. To understand the roles of miRNAs in ROP model rats, we constructed two small RNA libraries from the plasma of hyperoxia-induced rats and normal controls. Sequencing data revealed that 44 down-regulated microRNAs and 22 up-regulated microRNAs from the hyperoxia-induced rats were identified by deep sequencing technology. Some of the differentially expressed miRNAs were confirmed by quantitative reverse transcription-PCR (qRT-PCR). A total of 594 target genes of the differentially expressed microRNAs were identified using a bioinformatics approach. Functional annotation analysis indicated that a number of pathways might be involved in angiogenesis, cell proliferation and cell differentiation, which might be involved in the genesis and development of ROP. The elevated expression level of the vascular endothelial growth factor (VEGF) protein in the hyperoxia-induced neonatal rats was also confirmed by enzyme linked immunosorbent assay (ELISA). This study provides some insights into the molecular mechanisms that underlie ROP development, thereby aiding the diagnosis and treatment of this disease.