Fig. 3

Human umbilical cord-derived mesenchymal stem cell exosomes (hucMSC-Ex) induce autophagy in NRK-52E cells in response to cisplatin. a Transmission electron microscopic examination of autophagosomes in NRK-52E cells. The representative images indicate typical autophagosomes in the cells treated with hucMSC-Ex (scale bar = 1 μm). b SIM examination of autophagosomes in NRK-52E cells. Yellow dots represents autophagosomes, red dots represent autolysosomes (scale bar = 5 μm). Representative images of fluorescent LC3 puncta are shown. c Western blotting analyses of the expression of the autophagic markers LC-3B and Beclin-1 in NRK-52E cells. d NRK-52E cells were treated as indicated and the expression of mammalian target of rapamycin (mTOR), phosphorylated mTOR, 4EBP-1, and P70S6K proteins was determined by Western blot. NRK-52E cells treated as mentioned for the in vitro experiment were divided into four groups: 1) control; 2) phosphate-buffered saline (PBS); 3) hucMSC-Ex; and 4) human fetal lung fibroblast-1exosomes (HFL1-Ex)