Sestrin2 Regulates Endoplasmic Reticulum Stress-Dependent Ferroptosis to Engage Pulmonary Fibrosis by Nuclear Factor Erythroid 2-Related Factor 2/Activating Transcription Factor 4 (NRF2/ATF4)

Figure 3

Activation of NRF2/ATF4 alleviates endoplasmic reticulum stress-dependent ferroptosis levels to reduce pulmonary fibrosis. (a) BiFC analysis of the interaction between NRF2 and ATF4 (scale bar = 20 µm, n = 3). (b and c) Western blot analysis of the expression of ATF4 and NRF2 (n = 3). (d) Western blot analysis of the expression of ER stress-related proteins (GRP78, CHOP, and XBP-1, n = 3). (e) Western blot analysis of the expression of ferroptosis-related proteins (GPX4, HO-1, and FTH1, n = 3). (f) Western blot analysis of the expression of FMT-related proteins (α-SMA, collagen-I, collagen-III, FN1, and E-cadherin, n = 3). (g and h) Immunofluorescence analysis of CHOP and α-SMA expression (scale bar = 20 µm, n = 3). (i) Flow cytometric analysis of ROS levels (n = 3). (j) Analysis of Fe²⁺ levels (n = 3). (k and l) Oxidative stress factor analysis to determine the expression of MDA and SOD (n = 3). (m) ELISA analysis of the expression of inflammation-related factors (IL-1β, IL-6, and TNF-α, n = 3) vs. NC, , vs. TGF-β1, ^#, ^##, ^### vs. TGF-β1 + oe-NRF2, ^&, ^&&, ^&&&.

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