UHPLC–MS analysis for bioactive compounds responsible for the anti-inflammation activities of Jiao Mei Gu on lipopolysaccharide-induced acute lung injury in mice

Objective To identify the anti-inflammatory ingredients of a typical Dong herbal medicine Jiao Mei Gu (JMG) (Cayratia albifolia C.L.Li) and reveal the underlying mechanisms. Methods For the first time, the chemical constituents in JMG ethyl acetate extract, which showed the highest anti-inflammatory activity, were analyzed by Ultra-performance liquid chromatography-quadrupole-electrostatic field Orbitrap mass spectrometry (UHPLC-Q-Exactive orbitrap MS). The anti-inflammatory activities and the underlying mechanisms of JMG extracts were evaluated in the lipopolysaccharide (LPS)-induced RAW 264.7 cell model and LPS (10 mg/kg) induced acute lung injury model in BALB/c mice. Key findings Overall, 65 compounds including lignans, apigenin, quercetin, chrysin, phlorizin, and eriodictyol, etc., were identified in JMG ethyl acetate extract. At 200 mg/kg, JMG ethyl acetate extract reversed the structure change of lung alveoli and inflammatory cell infiltration in LPS-induced acute lung injury model. Compared with the LPS group, the serum levels of IL-1β, IL-6, and TNF-α in the 200 mg/kg JMG-treated group were decreased by 58.6%, 56.5%, and 87.6%, respectively. Western blot results revealed that JMG ethyl acetate extract inhibited LPS stimulated p65 and IκBα phosphorylation in mouse lung. Conclusion The present study demonstrated that the ethyl acetate fraction of JMG could reverse LPS-induced acute lung hemorrhagic necrosis and inflammatory cell infiltration in mice by preventing the phosphorylation of NF-κB p65 and reducing its nuclear translocation.