Oxysophocarpine inhibits lung injury induced by respiratory syncytial virus.

Oxysophocarpine (OSC) has various pharmacological effects. This study was designed to investigate whether OSC confers protection against respiratory syncytial virus (RSV) infection-induced lung injury. Here, we found that OSC inhibited RSV replication and increased the viability of RSV-infected lung epithelial A549 cells. OSC suppressed the RSV-increased production and release of pro-inflammatory cytokines and chemokines [tumor necrosis factor-α, interleukin-6 (IL-6), IL-8, regulated on activation in normal T-cell expressed and secreted, macrophage inflammatory protein-1α; and monocyte chemoattractant protein-1] in A549 cells. OSC also reduced the formation of reactive oxygen species and enhanced the activities of antioxidant enzymes in RSV-infected cells. The anti-oxidative effect of OSC on RSV-infected cells was dependent on NF-E2-related factor 2 activation. In vivo, OSC significantly alleviated RSV-triggered mouse lung injury. Overall, these results indicated that OSC attenuates RSV-enhanced pulmonary damage by inhibiting oxidative stress and inflammation.