Western blot results showed that the relative quantification of CHOP (0.910 ± 0.053) and caspase-12 (1.104 ± 0.026) increased in the COPD group when compared with the normal control group (0.204 ± 0.021, 0.133 ± 0.013, t = -36.04, -115.03, P < 0.05), while the ratios of the resveratrol intervention group (0.462 ± 0.037, 0.642 ± 0.011) decreased significantly when compared with COPD group (t = 24.22, 60.59, P < 0.05).
Compared with COPD and donor lungs, protein levels of ER stress mediators, such as processed p50 activating transcription factor (ATF)-6 and ATF-4 and the apoptosis-inductor CHOP (C/EBP-homologous protein), as well as transcript levels of spliced X-box binding protein (XBP)-1, were significantly elevated in lung homogenates and type II alveolar epithelial cells (AECIIs) of IPF lungs.