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.