Fig. 3

MiR-371b-5p activates PI3K/Akt pathway in hiPSC-ATIICs. The cultured hiPSC-ATIICs were transfected with various doses of miR-371b-5p mimic as indicated. a Histogram representation of the number of viable cells in the cultures of miR-371b-5p mimic-treated hiPSC-ATIICs. b The miR-371b-5p mimic-transfected hiPSC-ATIICs were treated with BrdU for 12 hours to label the proliferating cells and then were immunostained with mouse anti-BrdU (red) and rabbit anti-SPC antibody (green). The BrdU-stained images were merged with SPC-stained images (left panel), and the BrdU⁺cells were counted and presented as the percentage of total cells in the miR-371b-5p mimic-treated cultures (right panel). c and d Western blot analysis of expression of Akt/pAkt and Erk/pErk in miR-371b-5p mimic-transfected hiPSC-ATIICs (top panel). The pAkt and pErk expression levels were quantified and presented as folds of control after being normalized to Akt and Erk, respectively (bottom panel). e Western blotting of Akt/pAkt, GSK3β/pGSK3β, FOXO3/pFOXO3, and FOXO1/pFOXO1 of hiPSC-ATIICs treated with miR-371b-5p mimic (150 pmol) using GAPDH as internal control. f The miR-371b-5p mimic-transfected hiPSC-ATIICs were incubated for 24 hours with and without LY294002 (25 μM). The number of viable cells in the cultures was counted 2 days after transfection. ATIICs alveolar epithelial type II cells, BrdU bromodeoxyuridine, DAPI 4′,6-diamidino-2-phenylindole, SPC surfactant protein C