ABSTRACT
Liriodendron chinense has been widely utilized in traditional Chinese medicine to treat dispelling wind and dampness and used for alleviating cough and diminishing inflammation. However, the antioxidant, antimicrobial, and anti-inflammatory effects of L. chinense leaves and the key active constituents remained elusive. So, we conducted some experiments to support the application of L. chinense in traditional Chinese medicine by investigating the antioxidant, antibacterial, and anti-inflammatory abilities, and to identify the potential key constituents responsible for the activities. The ethanol extract of L. chinense leaves (LCLE) was isolated and extracted, and assays measuring ferric reducing antioxidant power, total reducing power, DPPHâ¢, ABTSâ¢+, and â¢OH were used to assess its in vitro antioxidant capacities. Antimicrobial activities of LCLE were investigated by minimal inhibitory levels, minimum antibacterial concentrations, disc diffusion test, and scanning electron microscope examination. Further, in vivo experiments including macro indicators examination, histopathological examination, and biochemical parameters measurement were conducted to investigate the effects of LCLE on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. LCLE was further isolated and purified through column chromatography, and LPS-induced RAW264.7 cells were constructed to assess the diminished inflammation potential of the identified chemical composites. ABTSâ¢+ and â¢OH radicals were extensively neutralized by the LCLE treatment. LCLE administration also presented broad-spectrum antimicrobial properties, especially against Staphylococcus epidermidis by disrupting cell walls. LPS-induced ALI in mice was significantly ameliorated by LCLE intervention, as evidenced by the histological changes in the lung and liver tissues as well as the reductions of nitric oxide (NO), TNF-α, and IL-6 production. Furthermore, three novel compounds including fragransin B2, liriodendritol, and rhamnocitrin were isolated, purified, and identified from LCLE. These three compounds exhibited differential regulation on NO accumulation and IL-10, IL-1ß, IL-6, TNF-α, COX-2, and iNOS mRNA expression in RAW264.7 cells induced by LPS. Fragransin B2 was more effective in inhibiting TNF-α mRNA expression, while rhamnocitrin was more powerful in inhibiting IL-6 mRNA expression. LCLE had significant antioxidant, antimicrobial, and anti-inflammatory effects. Fragransin B2, liriodendritol, and rhamnocitrin were probably key active constituents of LCLE, which might act synergistically to treat inflammatory-related disorders. This study provided a valuable view of the healing potential of L. chinense leaves in curing inflammatory diseases.
ABSTRACT
This study was sought to investigate the chemical composition and antibacterial and antiulcerative colitis (UC) effects of essential oil from Pruni Semen (PSEO). A GC-MS assay showed that the major compounds in PSEO were products of amygdalin hydrolysis, which possessed great antibacterial and anti-inflammatory potential. In vitro antibacterial experiments demonstrated that PSEO treatment inhibited activity of four kinds of intestinal pathogens probably by disrupting the cell wall. Further in vivo studies showed that PSEO administration significantly improved physiological indexes, attenuated histopathological characteristics, and inhibited proinflammatory cytokine production in dextran sulfate sodium (DSS)-induced UC mice. Network pharmacology and molecular docking results predicted that PSEO might prevent UC via regulating the PI3K/AKT pathway. Western blotting and immunofluorescence assays were further conducted for verification, and the results evidenced that PSEO intervention significantly regulated the PI3K/AKT pathway and the expression of its downstream proteins in DSS-induced mice. PSEO might provide a new dietary strategy for UC treatment.
