Fig. 5

Senescent epithelial cells-derived exosome miR-217-5p directly targets SIRT1 in fibroblasts. A qPCR analysis of the mRNAs expression of Sirt1 in pulmonary fibroblasts treated with the exosomes isolated from MLE-12 cells (MLE-12 Exo) or PQ-treated MLE-12 cells (PQ-MLE-12 Exo). B Western blot analysis of SIRT1 expression in pulmonary fibroblasts treated with MLE-12 Exo or PQ-MLE-12 Exo. C, D qPCR (C) and Western blot (D) analysis of SIRT1 expression in pulmonary fibroblasts transfected with or without miR-217-5p mimic. E Relative luciferase activity analysis in pulmonary fibroblasts co-transfected with wide type (WT) or mutant type (MUT) SIRT1-3’UTR reporters together with miR-217-5p mimic or negative control (NC). F Relative luciferase activity analysis in SIRT1-WT-transfected pulmonary fibroblasts that were further treated with MLE-12 Exo or PQ-MLE-12. G, H qPCR (G) and Western blot (H) analysis of the expression of SIRT1, α-SMA and Collagen I in pulmonary fibroblasts transfected with or without SIRT1 siRNAs (si-SIRT1). I EdU assay for the proliferation of pulmonary fibroblasts transfected with or without si-SIRT1. J, K qPCR (J) and Western blot (K) analysis of the expression of SIRT1, α-SMA and Collagen I in pulmonary fibroblasts transfected with or without miR-217-5p mimic and co-transfected with or without LV-SIRT1. All data were presented as the means ± SEM. *P < 0.05, *P < 0.01