MicroRNA profiling from the silica-induced pulmonary fibrosis mouse model

microRNAs (miRNAs) play a critical biological role in a variety of pathophysiological processes by suppressing their target genes. However, little is known on the miRNAs expression profiles of lung tissues in silica-induced pulmonary fibrosis. To investigate miRNAs of interest in regulation of pulmonary fibrosis, total RNA was isolated from mice lungs collected at day 0, day 3, day 7, day 14, day 28 and day 56 after silica exposure. Then, miRNA microarray was performed with one mouse lung at each time point. miRNA microarray was performed with one mouse lung at day 0, day 3, day 7, day 14, day 28 and day 56 after silica exposure to investigate the miRNAs expression profiles of lung tissues in silica-induced pulmonary fibrosis. Mouse lung tissues were selected at each time point after treatment for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain homogeneous populations of lungs at each fibrotic stage in order to increase the temporal resolution of expression profiles. To that end, we hand-selected lung tissues according to morphological criteria at five time-points: before silica exposure, i.e. day 0 (D0), the early inflammation phase day 3 (D3) and day 7 (D7), the late inflammation phase, day 14 (D14), the fibrosis phase,i.e. day 28 (D28) and day (D56).