Expression profile of circular RNAs in blood samples of Northern Chinese males with intracerebral hemorrhage shows downregulation of hsa-circ-0090829

Abstract

Circular RNAs (circRNAs) are involved in several neurological disorders; however, the mechanisms underlying their involvement remain to be clarified. We attempted to explore the expression profiles of circRNAs and their potential functions and mechanisms in the pathogenesis of intracerebral hemorrhage (ICH) in Northern Chinese males. The microarray results showed that 50 circRNAs were significantly upregulated, while 194 circRNAs were significantly downregulated in ICH patients compared with healthy controls (p < 0.05). After bioinformatics analysis, a circRNA-microRNA-messenger RNA network and a protein-protein interaction network were constructed. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that the neurotrophin signaling pathway, long-term potentiation, and the mitogen-activated protein kinase pathway are potentially implicated in ICH pathophysiology. The quantitative real-time polymerase chain reaction results revealed that hsa-circ-0090829 was significantly downregulated in ICH. The receiver operating characteristic curve analysis showed that the area under the curve of hsa-circ-0090829 between ICH and healthy controls was 0.807. Furthermore, the dual-luciferase assay showed that hsa-circ-0090829 sponged miR-526b-5p. This study reports the altered expression of circRNAs and identifies the potential functions of these circRNAs in ICH. Our results may facilitate further mechanistic research on circRNAs in ICH and provide probable novel diagnostic biomarkers and therapeutic targets for ICH.

Keywords: Diagnostic biomarker; GO enrichment; Hsa-circ-0090829; Intracerebral hemorrhage; KEGG pathway; ceRNA.

Fig. 1

Flowchart of the enrolment of patients with ICH.

Fig. 2

Differential expression of circRNAs in the blood between patients with ICH and healthy controls. A. Differentially expressed circRNAs shown using a volcano plot. Fifty circRNAs were significantly upregulated, while 194 circRNAs were significantly downregulated in patients with ICH compared with healthy controls. B. The expression patterns of the top 10 circRNAs between patients with ICH and healthy controls shown by the hierarchical clustering heatmap. Hsa-circ-0090829 was significantly downregulated in patients with ICH.

Fig. 3

Expression and ROC curve of hsa-circ-0090829. A. Boxplot indicating the relative expression of hsa-circ-0090829 between patients with ICH and healthy controls using qRT-PCR (U test *p < 0.05). B. ROC curve of hsa-circ-0090829 to differentiate patients with ICH from healthy controls (*p < 0.05). The X axis indicates the false-positive rate. The left Y axis indicates the true-positive rate. The right Y axis indicates the relative expression value.

Fig. 4

Plasmid construction and results of the dual-luciferase assay. A. Hsa-circ-0090829 (WT) plasmid. B. Hsa-circ-0090829 (MUT) plasmid. C. The miR-526b-5p mimic significantly decreased hsa-circ-0090829 (WT)-mediated luciferase activity (T test *p < 0.05) compared to NC, but it had no effect on hsa-circ-0090829 (MUT)-mediated activity. D. The miR-486-3p mimic did not significantly decrease hsa-circ-0090829 (WT)-mediated luciferase activity.

Fig. 5

Hsa-circ-0090829–miR-526b-5p–mRNA ceRNA network.

Fig. 6

GO and KEGG pathway enrichment results of miR-526b-5p target genes (*p < 0.05). A. GO enrichment results of miR-526-5p target genes. B. KEGG pathways enriched by miR-526b-5p target genes.

Fig. 7

PPI network of miR-526b-5p target genes.