Figures & data
Figure 1. The expression of tPA is upregulated in lung tissues from bleomycin-induced mice. (a) The lung sections from the mice after different periods of bleomycin treatment were stained by hematoxylin-eosin (H&E) and Masson. (b) The expression of α-smooth muscle actin (α-SMA), collagen and β-catenin after different periods of bleomycin treatment was determined by western blot and represented graphically viz-a-viz the control. (c) The protein level of tPA after different periods of bleomycin treatment was determined by western blot. (d) The expression of tPA in lung tissues was examined by immunofluorescence assay. Nuclei were stained with DAPI (blue). (e) The expression of tPA in lung tissues was examined by immunohistochemical staining
Figure 2. tPA promotes lung interstitial fibroblast proliferation via sequential phosphorylation of Erk1/2, p90RSK, GSK-3β, and induction of Cyclin D1. (a) The change of cell proliferation was observed with the cell counting kit (CCK-8) assay. *P ≤ 0.05 versus control. (b-c) Cells were incubated with tPA (20 nM) for various periods of time as indicated and then subjected to western blot for phospho-Erk1/2 and phospho-p90RSK (Ser9). (d-e) Cells were treated with tPA (20 nM) for different periods of time and the protein levels of phospho-GSK-3β (Ser380) and cyclin D1were assessed via western blot
Figure 3. The effect of tPA on Wnt/β-catenin signaling pathway. (a) Primary lung fibroblasts were treated with 20 nM tPA for different periods of time and the expression levels of phospho-GSK-3β (Ser9) and β-catenin were assessed by western blot. (b) Primary lung fibroblasts were pretreated with tPA inhibitor PAI (5 nM) for 1 h and subsequently exposed to tPA (20 nM) for 48 h, then subjected to western blot for p-GSK-3β (Ser9) and β-catenin. (c) Primary lung fibroblasts were pretreated with inhibitor PD98059 at 20 μg/ml for 1 h and subsequently exposed to tPA (20 nM) for 48 h; expressions of p-GSK-3β (Ser9) and β-catenin were assessed by western blot
Figure 4. Effects of PD98059 on Wnt/β-catenin signaling pathway in animals. (a) Protein levels of p-Erk、p-p90RSK (Ser380)、p-GSK-3β (Ser9) and CyclinD1 in lung tissues from bleomycin-induced mice were assessed via western blot. (b) Bleomycin-induced mice were treated intraperitoneally PD98059 (20 μg/kg) for 14 days then subjected to western blot for the expression levels of p-GSK-3β (Ser9) and β-catenin. (c) Representative pictures of lung sections from the control group and PD98059-treated group with H&E and Masson’s trichrome staining
Figure 5. Schematic representation of role of tPA in the proliferative signaling and Wnt/β-catenin signaling
