RESUMO
Coronary heart disease (CHD) is a prevalent global cause of death. Research suggests that circular RNAs (circRNAs) play a role in the development of CHD. In this study, we investigated the expression of hsa_circRNA_0000284 in peripheral blood leukocytes (PBLs) obtained from a cohort of 94 CHD patients aged over 50 years, as well as 126 age-matched healthy controls (HC). An in vitro inflammatory and oxidative injury cell model that simulates CHD was used to evaluate changes in hsa_ circRNA _0000284 under stress. CRISPR/Cas9 technology was used to evaluate changes in hsa_circRNA_0000284 expression. An hsa_ circRNA_0000284 overexpression and silencing cell model was used to analyze the biological functions of hsa_circRNA_0000284. Bioinformatics, qRT-PCR, viral transfection technology, and luciferase assays were used to evaluate the potential hsa_circRNA_0000284/miRNA-338-3p/ETS1 axis. Western blotting analysis was performed to detect protein expression. Herein, PBLs from CHD patients exhibited downregulation of hsa_circRNA_0000284 expression. Exposure to oxidative stress and inflammation can induce damage to human umbilical endothelial cells, resulting in the downregulation of hsa_circRNA_0000284 expression. The expression of hsa_circRNA_0000284 in EA-hy926 cells was significantly reduced after the AluSq2 element of hsa_circRNA_0000284 had been knocked out. The expression of hsa_circRNA_0000284 affected proliferation, cycle distribution, aging, and apoptosis in EA-hy926 cells. Consistent with the results of cell transfection experiments and luciferase assays, Western blotting showed that hsa_circRNA_0000284 plays a role in the regulation of hsa-miRNA-338-3p expression. Subsequently, hsa-miRNA-338-3p was found to be involved in the regulation of ETS1 expression.Communicated by Ramaswamy H. Sarma.
RESUMO
Objects: To evaluate the hsa_circ_0001445 level in peripheral blood leukocytes of patients with coronary heart disease (CHD) and its related clinical factors, and predict its circRNA-miRNA-mRNA regulatory network in CHD pathogenesis via bioinformatics analysis. Methods: Peripheral blood leukocytes were isolated from the whole blood samples of 94 CHD patients (aged 65.96 ± 9.78 years old) and 126 healthy controls (aged 60.75 ± 8.81 years old). qRT-PCR was used to quantify the expression level of circRNA and subsequently analyze its association with CHD clinical parameters. Via bioinformatics algorithm and GEO datasets, differential miRNA expression was evaluated using the Limma package. A miRNA-mRNA regulatory network was predicted by cyTargetLinker. ClusterProfiler was employed to perform functional enrichment analysis of the circRNA network to investigate its role in CHD pathogenesis. Results: The expression of hsa_circ_0001445 in peripheral blood leukocytes of CHD patients was downregulated compared with that of healthy controls. Positive correlations were evident between hsa_circ_0001445 expression level and the levels of hemoglobin, triglycerides, high- and low-density lipoprotein cholesterol. A significant negative correlation was also found between hsa_circ_0001445 expression level and age and the neutrophil level. Low expression of hsa_circ_0001445 exhibited a discriminatory ability between CHD patients and healthy controls with a sensitivity of 67.5% and a specificity of 76.6% (p < 0.05). By bioinformatics analysis, 405 gene ontology terms were identified. The Kyoto Encyclopedia of Genes and Genomes terms focused principally on the PI3K-Akt signaling pathway. hsa_circ_0001445 was associated with the expression of three miRNAs that may regulate 18 genes involved in KEGG processes: hsa-miR-507, hsa-miR-375-3p, and hsa-miR-942-5p. Conclusion: The hsa_circ_0001445 level in peripheral blood leukocytes may serve as a biomarker for CHD diagnosis. Our work on circRNA-miRNA-mRNA networks suggests a potential role for hsa_circ_0001445 in CHD development.
