CSF2 and acute respiratory distress syndrome: LEfSe analysis showed that DYY may modulate the Firmicutes/Bacteroidetes ratio to enhance granulocyte–macrophage colony-stimulating factor (GM-CSF) signal transduction and activate alveolar macrophages via extracellular signal-regulated kinase (ERK) specific signals, leading to increased ROS activity and reduced lung inflammation, ultimately contributing to the anti-ALI effect (Dillon et al., 2014).