RNA sequencing and bioinformatics analysis of circular RNAs in asphyxial newborns with acute kidney injury

As one kind of novel noncoding RNA, circular RNAs (circRNAs) are involved in different biological processes. Although growing evidences have supported the important role of circRNAs in renal diseases, the mechanism remains unclear in neonatal acute kidney injury (AKI). High-throughput sequencing analysis was used to investigate the expression of circRNAs between hypoxia-induced AKI neonates and controls. Bioinformatics analysis was conducted to predict the function of differentially expressed circRNAs. Finally, the differentially expressed circRNAs were screened and determined by quantitative real-time PCR (qPCR). (1) A total of 296 differentially expressed circRNAs were identified (Fold change >2 and p < 0.05). Of them, 184 circRNAs were markedly upregulated, and 112 were significantly downregulated in the AKI group. (2) The pathway analysis showed that ubiquitin-mediated proteolysis, renal cell carcinoma, Jak-STAT, and HIF-1 signaling pathways participated in AKI. (3) Top five upregulated and five downregulated circRNAs with higher fold changes were selected for qPCR validation. Hsa_circ_0008898 (Fold Change = 5.48, p = 0.0376) and hsa_circ_0005519 (Fold Change = 4.65, p = 0.0071) were significantly upregulated, while hsa_circ_0132279 (Fold Change = -4.47, p = 0.0008), hsa_circ_0112327 (Fold Change = -4.26, p = 0.0048), and hsa_circ_0017647 (Fold Change = -4.15, p = 0.0313) were significantly downregulated in asphyxia-induced AKI group compared with the control group. This study could contribute to future research on neonatal AKI and facilitate the identification of novel therapeutic targets.