TITLE:
MicroRNA Expression Profiles in the Neonatal Rat Hippocampus Exposed to Normobaric Hyperoxia
AUTHORS:
Yuewei Xia, Tong Liu, Ruolin Zhang, Tao Bo
KEYWORDS:
Normobaric Hyperoxia, MicroRNA, Neonate, Brain Injury, Hippocampus
JOURNAL NAME:
Open Journal of Pediatrics,
Vol.14 No.6,
November
8,
2024
ABSTRACT: Objective: This study aimed to identify differentially expressed microRNAs (miRNAs) using microarray and to predict special target genes using bioinformatics methods in the neonatal rat hippocampus after normobaric hyperoxia exposure, and to unravel the molecular mechanisms of developing brain injury induced by normobaric hyperoxia. Methods: Eight neonatal Sprague-Dawley rats at postnatal 1 day were divided equally between a control group and an experimental group, followed by 24-hour exposure to 21% oxygen and (95 ± 5) % oxygen, respectively. Total RNAs were extracted from the rat hippocampus. Three samples were randomly selected from each group to detect differentially expressed mRNA profiles using the affymetrix GeneChip Rat Genome 230 2.0 Array. Differentially expressed miRNA profiles were determined by miRNA enrichment analysis. The starBase software was applied to predict target genes abundantly expressed in the hippocampus, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted for bioinformatics analysis. Results: Microarray analysis revealed 681 differentially expressed miRNAs in the neonatal rat hippocampus after normobaric hyperoxia exposure. Only one miRNA, miR-489-5p, was significantly upregulated (P Mdfic. The other 680 miRNAs were significantly downregulated (P P Gjb6 and Bnc2. KEGG analysis indicated that differentially expressed miRNAs were closely related to multiple signaling pathways. Conclusions: Differentially expressed miRNA profiles in the neonatal rat hippocampus after normobaric hyperoxia exposure may be involved in the physiopathological processes of developmental midbrain injury induced by normobaric hyperoxia.