Lycorine destabilizes lipid rafts to inhibit inflammation via LXRα
signal in the lung of mice
Abstract
Background and Purpose: Lycorine is an alkaloid that was in the bulb of
the genus Lycoris. It has properties of anti-inflammatory. This study
aimed to investigate the molecular mechanism by which lycorine can
reduce acute lung injury (ALI). Experimental Approach: ALI model was
established by intranasal injection of lipopolysaccharide (LPS). In
vitro, A549 cells were treated with LPS and pretreated with lycorine for
1 hour. Key Results: The results showed that lycorine reduced
histopathological changes in lung, myeloperoxidase (MPO) activity, and
the production of inflammatory cytokines such as TNF-α, IL-1β, and IL-6
in mice. Lycorine dose-dependently inhibited the production of TNF-α,
IL-1β, and IL-6. It also inhibited the transmission of TLR4/NF-κB
passway in LPS-stimulated A549 cells. Lycorine increased cholesterol
efflux through the activated LXRα-ABCA1/ABCG pathway. Lycorine has a
good binding ability with LXRα. After adding the LXRα inhibitor, the
anti-inflammatory effect of lycorine was eliminated. Conclusion and
Implications: Lycorine can reduce ALI that was induced by
lipopolysaccharide. The anti-inflammatory mechanism of lycorine is
related to the up-regulation of the LXRα-ABCA1/ABCG pathway, which
inhibits TLR4-mediated inflammation by increasing cholesterol efflux and
reducing TLR4 transport to lipid rafts.