In addition, luteolin promotes the ERK1/2 signaling pathway, Ca2+ efflux, and HO-1 expression in macrophages and inhibits the inflammatory response to alleviate ALI, which also promotes macrophage polarization to the M2 type in ALI by promoting regulatory T cell differentiation for IL-10 expression [32,121]. Here, HMOX1 is linked to acute respiratory distress syndrome.