10-Hydroxy-2-decenoic acid ameliorates LPS-induced acute lung injury through targeting MD2-mediated inflammatory signaling pathways
Abstract
Background
Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), are life-threatening conditions with high mortality, characterized by excessive inflammatory responses. Lipopolysaccharide (LPS) is widely used to mimic ALI by activating myeloid differentiation factor 2 (MD2)/Toll-like receptor 4 (TLR4)-mediated inflammatory pathways. Royal jelly-derived 10-hydroxy-2-decenoic acid (10-HDA) exhibits anti-inflammatory properties, but its role in ALI remains unexplored.
Objective
This study aimed to investigate the therapeutic potential of 10-HDA against LPS-induced ALI and elucidate its underlying mechanism.
Methods
In vitro, mouse peritoneal macrophages (MPMs) were pretreated with 10-HDA before LPS stimulation. In vivo, ALI was induced in mice via intratracheal LPS, with 10-HDA administered intraperitoneally. Cytokine levels were measured via ELISA and qPCR. Signaling pathways were analyzed by Western blot and immunofluorescence. Lung injury, inflammatory cell infiltration, and edema were assessed via histopathology, BALF analysis, and wet/dry ratio. Immunoprecipitation, molecular docking, and drug affinity-responsive target stability (DARTS) assays were used to identify the interaction between 10-HDA and MD2.
Results
10-HDA significantly suppressed LPS-induced proinflammatory cytokine secretion in MPMs and ALI mice, and inhibited phosphorylation of TAK1, MAPKs, TBK1 and NF-κB nuclear translocation. It attenuated lung histopathological damage, neutrophil infiltration, and edema. Mechanistically, 10-HDA disrupted MD2/TLR4-mediated inflammatory pathways by directly binding MD2, as confirmed by immunoprecipitation, DARTS, and molecular docking.
Conclusion
10-HDA alleviates LPS-induced ALI by targeting MD2 to block TLR4 signaling, thereby suppressing both MyD88-dependent (MAPKs/NF-κB) and TRIF-dependent (TBK1/IRF3) pathways. These findings highlight 10-HDA as a promising therapeutic candidate for ALI/ARDS.