PCSK1 and acute respiratory distress syndrome: Fer-1, Z-VAD, and Nec-1 could significantly reverse the decrease of cell viability caused by ALI, among which pretreatment of Fer-1 significantly improved the cell viability by 11% (Figure 3A) but Z-VAD and Nec-1 both only elevated the cell viability by about 6% (Figures 3B and 3C).