Fig. 6.

ARDS activates PERK and ISR signaling. a ER stress signaling was measured in protein extracts obtained from patients with ARDS and compared to non-ARDS (control). ARDS did not affect the expression of BiP,XBP-1and ATF6. We detected the phosphorylation of PERK, eIF2α and the increased expression of its downstream integrated stress response transcription factors ATF4 and CHOP. We did not detect significant change in GADD34 expression. We used total t-PERK for the loading control of p-PERK and t-eIF2 for p-eIF2α. All other protein expression was normalized to β-actin. b-i Quantified densitometry data is shown. Statistics: Kruskal-Wallis test was performed for multiple group comparison, and intergroup differences were analyzed with Wilcoxon rank sum test. Control samples N = 4, ARDS samples N = 5, p < 0.05. Data is presented as averaged values ±SEM in a five number summary format. *represents significant increase in p-PERK, p-eIF2α, ATF4 and CHOP in ARDS vs. control