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Objective
The main pathological change of myocarditis is an inflammatory injury of cardiomyocytes. Long noncoding RNAs (lncRNAs) are closely related to inflammation, and our previous study showed that differential expression of lncRNAs is associated with myocarditis. This study aimed to investigate the impact of lncRNAs on the onset of myocarditis.
Methods
RNA expression was measured by quantitative reverse-transcription polymerase chain reaction (RT-qPCR). Lipopolysaccharide (LPS) was used to induce inflammation in human cardiomyocytes (HCMs). The expression of inflammatory cytokines and myocardial injury markers was detected by enzyme-linked immunosorbent assay (ELISA) and RT-qPCR. Cell viability and apoptosis were measured by the cell counting kit-8 assay and flow cytometry. The binding force between lncRNA NONHSAT122636.2 and microRNA miRNA-2110 was detected using the dual-luciferase assay.
Results
NONHSAT122636.2 was dynamically expressed in patients with myocarditis and negatively correlated with inflammation severity. The overexpression of NONHSAT122636.2 improved inflammatory injury in LPS-stimulated HCMs. The study observed that there was a weak binding force between NONHSAT122636.2 and miR-2110.
Conclusion
NONHSAT122636.2 attenuates myocardial inflammation and apoptosis in myocarditis. Additionally, its expression decreases in the peripheral blood of children suffering from myocarditis and in patients who are diagnosed for the first time showing higher diagnostic sensitivity and specificity. This decrease is negatively correlated with the degree of inflammation. Overall, the study suggests that NONHSAT122636.2 can be exploited as a potential diagnostic biomarker for pediatric myocarditis.