Expression profiling of miRNAs in chrysotile-exposed lung epithelial cells

BackgroundChrysotile is widely used in construction and industry. Research has shown that it is associated with lung fibrosis in occupational groups, but the involvement of microRNAs (miRNAs) in chrysotile-induced lung fibrosis has been less well studied, and the specific mechanism is still unclear. ObjectiveUsing next-generation sequencing technology to analyze the effects of chrysotile exposure on the miRNAs expression profiles of human lung epithelial cells (BEAS-2B cells), to explore the variations of differentially expressed miRNAs and related signaling pathways, and to identify potential targets and molecular mechanisms of chrysotile-induced lung fibrosis. MethodsChrysotile was analyzed with a laser particle size analyzer and an X-ray diffractometer for particle size and physical phase. BEAS-2B cells were exposed to chrysotile for designed time sessions (12, 24, and 48 h) and doses (0, 50, 100, and 200 μg·mL−1). Cell viability was detected with a cell viability assay kit (CCK8); expression levels of Fibronectin, Collagen-Ⅰ, and α-smooth muscle actin (α-SMA) were detected by Western blot after exposure to 200 μg·mL−1 chrysotile for 24 h. Sample correlation and changes in miRNAs expression profiles between the chrysotile-exposed and the control groups were analyzed by next-generation sequencing technology. The target genes of differentially expressed miRNAs were predicted and subjected to Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. ResultsThe average particle size of the chrysotile dust sample used in this study was 3.58 μm, and the results of X-ray diffraction analysis confirmed the characteristic peaks of chrysotile. Compared with the control group, the chrysotile gradually inhibited the survival rate of BEAS-2B cells with increasing concentration and exposure time (P