Mesenchymal Stem Cells Inhibit Epithelial-to-Mesenchymal Transition by Modulating the IRE1α Branch of the Endoplasmic Reticulum Stress Response

Figure 4

MSCs ameliorated ER stress in A549 cells. A549 cells were treated with 10 ng/ml TGF-β1 in the presence or absence of MSCs for 72 hr. (a) The protein expression levels of BiP, ATF6, ATF4, XBP-1s and XBP-1u were measured using western blotting and quantified using densitometry in ImageJ software (n = 3, one-way ANOVA with Duncan’s post hoc test). (b) The mRNA expression levels of BiP, ATF4, ATF6, XBP-1s and CHOP were measured using Q-PCR (n = 3, one-way ANOVA with Duncan’s post hoc test). (c) A549 cells were cocultured with MSCs in the absence of TGF-β1 for different times, and the protein expression levels of BiP, ATF6, ATF4, XBP-1s and XBP-1u were measured using western blotting. The results were quantified using densitometry in ImageJ software (n = 3, one-way ANOVA with Duncan’s post hoc test). (d) Cellular ultrastructure in the different groups. The arrows indicate the ER. Scale bar, 500 nm. The data are shown as the means ± SEMs (, , vs. the control group; ^###, ^##, ^# vs. the TGF-β1 group).

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