Fig. 4

Effect of hypoxic preconditioning (HPC) on the autophagy of BM-MSCs. a Representative electron micrographs revealed the autophagic vacuole formation in BM-MSCs. b Quantification of the average numbers of the autophagic structures in the cytoplasm. c Autophagy flux was analyzed in BM-MSCs infected with Ad-GFP-LC3 adenovirus. Representative immunofluorescence images of green fluorescent protein (GFP)-LC3 (green fluorescence) and 4,6-diamidino-2-phenylindole (DAPI) (blue fluorescence) in BM-MSCs with HPC for the indicated time points. Scale bars = 20 μm. d Quantification of autophagy flux was presented as the percentage of BM-MSCs with punctate LC3 in all groups. e Representative Western blots of LC3-I/LC3-II, Beclin-1, and P62 in BM-MSCs with HPC for 0 h, 12 h, 24 h, 36 h, and 48 h, respectively. Semiquantification of the protein expressions of LC3-II (f), Beclin-1 (g), and p62 (h) at the indicated time points. Data are expressed as means ± SEM; n = 5; *p < 0.05