Study on the value and mechanism of miR-369-5p in childhood pneumonia

Childhood pneumonia (CP) represents a leading cause of pediatric mortality globally. Consequently, prompt diagnosis of CP is of great significance for its treatment and prognosis. The objective of this study is to investigate the clinical significance of miR-369-5p in CP and its underlying mechanism. This study enrolled clinical data from 69 CP patients and 60 healthy individuals. Through binary logistic analysis, ROC analysis, and Kaplan-Meier (KM) analysis, the diagnostic and prognostic utility of miR-369-5p for CP was determined. The RT-qPCR experiment was used to detect the expression levels of miR-369-5p, polymeric immunoglobulin receptor (PIGR), and inflammatory cytokines. The study used LPS (Lipopolysaccharide) to induce WI-38 cells to establish a pneumonia cell model for in vitro cell experiments and used the kit to detect the oxidative stress indicators. The cell proliferation and apoptosis were detected through CCK8 (Cell Counting Kit-8) and flow cytometry assays. The target genes of miR-369-5p were predicted using TargetScan database and subsequently validated via dual luciferase reporter assays. Pearson analysis revealed the correlation between miR-369-5p and PIGR. MiR-369-5p was markedly overexpressed in CP, serving as a diagnostic biomarker for CP, as well as being associated with a poor prognosis. LPS induction in WI-38 cells triggered miR-369-5p upregulation, which coincided with enhanced levels of inflammation, oxidative stress indicators and apoptosis, and a decline in proliferation capacity. PIGR was confirmed as a downstream target of miR-369-5p. Silencing miR-369-5p could lead to increased expression of PIGR, decreased expression of inflammatory factors and oxidative stress indicators, and enhanced cell activity. Meanwhile, inhibition of PIGR could weaken the effect of inhibiting miR-369-5p. Upregulated serum miR-369-5p serves as a promising non-invasive biomarker for the diagnosis and prognosis of CP. Inhibiting miR-369-5p can ameliorates the condition of CP by targeting PIGR.