Exosomal miRNA Let-7 from Menstrual Blood-Derived Endometrial Stem Cells Alleviates Pulmonary Fibrosis through Regulating Mitochondrial DNA Damage

Figure 4

Effect of Let-7 modification on alveolar epithelial cell injury and pulmonary fibrosis. (a) Cells were firstly transfected with Let-7 NC/inhibitor for 24 h. Then, the relative level of ROS in MLE-12 cells exposed to TGF-β1, TGF-β1 plus exosome, and three combinations of TGF-β1, exosome (48 h), and Let-7 inhibitor or Let-7 NC inhibitor was determined by flow cytometry using DCFH-DA ROS fluorescence probe (). (b) mtDNA damage in MLE-12 cells of each group as measured by PCR (). (c) HE staining and Masson staining were performed in mice exposed to saline, BLM, BLM plus exosome, BLM plus exosome and negative control of Let-7, and BLM plus exosome and Let-7 inhibitor (). Scale bar, 200 μm. (d) Fibrotic area in the five groups was fully quantified ( per group). (e) Ashcroft scores, (f) dry and wet weight ratio of lung tissue, and (g) hydroxyproline detection in the mouse lung tissue of four different groups ( per group). (h) Measurements of malondialdehyde (MDA) content and (i) glutathione peroxidase (GSH-Px) level in mouse lung tissue using their corresponding detection kits. (j) The expression level of ROS in the lung tissue of each group as assessed by flow cytometry using a DCFH-DA assay. (k) Statistics of mtDNA damage in lung tissues of mice in each group ( per group). Data is shown as the . and .

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