FIGURE 1.

ALI induced by mechanical ventilation is associated with reduced activity of SDHA in alveolar epithelium. A, Schematic overview of ventilation experiments: 10‐ to 12‐week‐old mice were anesthetized and ventilated for 4 h with the following parameters: Pressure‐controlled ventilation (PCV), peak inspiratory pressure (PIP) 15 cm H₂O in the control group and 45 cm H₂O in the experimental group, PEEP 3 cm H₂O, respiratory rate 80/min, and FiO₂ 1.0 were set equally in both groups. B and C, TCA cycle intermediates succinate and fumarate were determined with mass spectroscopy in ATII cells after mice were exposed to 15 or 45 cm H₂O PIP. D, Succinate dehydrogenase (SDHA) activity was determined by calculating the succinate to fumarate ratio. mRNA expression of SDH subunits (E) and Irg‐1(F) was determined with qPCR. (G) Itaconate abundance was measured in ATII cells via mass spectroscopy. Data are represented as mean ± SD, n = 3‐4, ns‐not significant, *P <.05, **P <.01, Welch's t test in F, t = 5.993 and df = 3.09; two‐sample t test in G, t = 3.43 and df = 5. A total of 21 animals were used