Diagnosis and Mechanism of miR-1224-5p in Children With Mycoplasma pneumoniae Pneumonia Complicated by Digestive System Damage.

Pediatric Mycoplasma pneumoniae pneumonia (MPP) is often complicated by digestive system damage (DSD), with unclear mechanisms and biomarkers. The role of miR-1224-5p in this remains unknown. To explore the diagnostic value, mechanism, and role of miR-1224-5p in lung-gut axis injury in MPP + DSD. Bioinformatics analysis screened miR-1224-5p. Serum levels were detected via RT-qPCR in 120 MPP children (57 with DSD) and 81 controls. ROC curves and logistic regression assessed its diagnostic value. LAMPs-induced cell models and co-cultures were used to explore the mechanisms. GO/KEGG-analyzed pathways. Dual-luciferase assay was used to verify the binding relationship of the target. Serum miR-1224-5p was significantly upregulated in MPP children, especially in those complicated by DSD. MiR-1224-5p showed good diagnostic efficacy for MPP and MPP + DSD, and was an independent risk factor for DSD. In LAMPs-induced BEAS-2B cells and co-culture systems, miR-1224-5p expression was upregulated, while its inhibition reduced apoptosis and the secretion of inflammatory factors (IL-6, IL-1β, TNF-α). Its predicted target genes are involved in endothelial barrier, and GRB2 is a target of miR-1224-5p. MiR-1224-5p is a potential biomarker for MPP + DSD, and it participates in lung-gut injury by regulating inflammation/barrier function.