Fig. 3

Increased activation of autophagy in LPS-induced lung injury. A LC3 II/I expression in lung tissues under LPS stimulation for different hours and Immunochemistry was performed with LC3 II/I antibody. Images × 40 magnification, scale bar 50 μm. B Immunoblots of Beclin1 and LC3II/I were performed in mice lungs upon LPS treated at the indicated time, n ≥ 3 examinations. C Immunochemistry of LC3 II/I expression in lung tissues upon LPS treated when being pretreated with or without 3-MA. Images × 40 magnification, scale bar 50 μm. D The protein levels of Beclin1 and LC3II/I in mice lungs upon LPS treated when being pretreated with or without 3-MA performed by western blotting, n ≥ 3 examinations. E Transmission electron microscopy was used to observe the autophagic body. Red arrows indicate the number and location of autophagosomes. The scale bar for original images is 1 µm; the scale bar for enlarged images is 500 nm. F HE staining images of mouse lung sections (images × 40 magnification, scale bar 50 μm). The apoptosis of lung cells was evaluated. The lung sections were fixed and immunostained by the TUNEL assay and caught images by spinning disk confocal microscopy at × 40 magnification (scale bar 50 μm) and × 200 magnification (scale bar 10 μm). * Indicates the significant difference compared with the Control group, # indicates the significant difference compared with the LPS group. P < 0.05, differences in characteristics between groups were analyzed using the Kruskal–Wallis test with Dunn’s post hoc tests