Fig. 4

Hypo-EV treatment prevented the airway and lung parenchyma fibrosis in chronic asthma mice. a Representative photomicrographs of airway (upper panels) and lung parenchyma (lower panels) stained with Masson trichrome staining (black bar = 200 μm). b Percentage of collagen fiber content in airway and lung parenchyma (n = 6). *P < 0.05, **P < 0.01, ***P < 0.001. c Collagen levels in lung tissue determined by hydroxyproline assay (n = 6). *P < 0.05, **P < 0.01, ***P < 0.001. d Representative Western blots of Col-1 and α-SMA (GAPDH was used as protein loading control) in the lungs from each group (n = 4), and band intensities were normalized against the corresponding GAPDH and the numbers are presented as fold increase over the control group. *P < 0.05, ***P < 0.01 vs. PBS group; #P < 0.05 vs. Nor-EV group