NFE2L2 and injury: We selected five Nrf-2/ARE- and NF-κB signaling pathway-related genes, including hmox1 heme oxygenase 1 (Ho-1), glutathione peroxidase 1 (GPX-1), nuclear factor, erythroid derived 2, like 2 (NRF-2), unclear factor kappa B subunit 1 (NF-kB), and glucocorticoid receptor (GR), to explore if MSC-exosomes could reverse LPS-induced acute lung injury through the Nrf-2/ARE and NF-κB signaling pathways.