MicroRNA expression in peripheral blood of children with asthma and the role of miR-31-5p in childhood asthma progression.

MicroRNAs (miRNAs) have emerged as critical epigenetic regulators in the pathogenesis of childhood bronchial asthma. This study employed high-throughput sequencing to explore miRNA expression profiles in an asthma cohort, with a focus on elucidating the functional mechanisms of key miRNAs. Notably, among the miRNAs validated by RT-qPCR, miR-31-5p exhibited the largest area under the curve (AUC) value and demonstrated significant anti-inflammatory effects in an OVA-induced allergic inflammation mouse model. Bioinformatics analysis and dual-luciferase reporter assays confirmed that TBXA2R is a direct target of miR-31-5p. Mechanistically, stimulation with house dust mite (HDM) and IL-4 downregulated miR-31-5p expression in A549 cells, accompanied by elevated levels of TBXA2R and eotaxins (CCL11, CCL24, CCL26). Conversely, overexpression of miR-31-5p suppressed TBXA2R-mediated eotaxin production. These findings highlight the significant role of miR-31-5p in peripheral blood mononuclear cells (PBMCs) of asthmatic children, suggesting its potential involvement in upregulating eotaxin expression in A549 cells through negative regulation of TBXA2R.