Acetylation of polysaccharide from Morchella angusticeps peck enhances its immune activation and anti-inflammatory activities in macrophage RAW264.7 cells

Food Chem Toxicol. 2019 Mar;125:38-45. doi: 10.1016/j.fct.2018.12.036. Epub 2018 Dec 24.


Morchella angusticeps Peck has been recognized as a resource of nutraceuticals and drug discovery. Three acetylated polysaccharides (Ac-PMEP1-3) with appropriate degree of substitution were obtained from Morchella angusticeps Peck, chemically characterized, and cultured with macrophage RAW264.7 cells to evaluate their immune activation and anti-inflammatory activities. Results of ultraviolet-visible spectroscopy and fourier-transform infrared showed these modifications were successful. Compared with the control group, PMEP and Ac-PMEP1-3 enhanced cell proliferation and the production of nitric oxide and tumor necrosis factor-α of RAW264.7 macrophages (cultured without lipopolysaccharide). Compared with PMEP, Ac-PMEP3 enhanced cell viability and NO production by inducing the degradation of cytoplasmic IκBα and nuclear translocation of NF-κB subunit p65 as well as the expression of iNOS and phosphorylated-p38. Moreover, in lipopolysaccharide-stimulated RAW264.7 macrophages, Ac-PMEP3 showed a stronger ability to suppress the overproduction of nitric oxide and tumor necrosis factor-α by down-regulating the level of nuclear NF-κB p65, iNOS, and phosphorylated-p38 and inhibiting the degradation of cytoplasmic IκBα. Therefore, Ac-PMEP enhanced immune activation and anti-inflammatory activities via nuclear factor κB and p38/mitogen-activated protein kinase signaling pathways.

Keywords: Acetylated polysaccharide; Anti-inflammatory; Immunomodulatory; Morchella angusticepes peck; Nuclear NF-κB; RAW264.7 cells.

MeSH terms

  • Acetylation
  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Ascomycota / metabolism*
  • Macrophages / drug effects*
  • Macrophages / immunology*
  • Macrophages / metabolism
  • Mice
  • Nitric Oxide / biosynthesis
  • Nitric Oxide / metabolism
  • Phagocytosis / drug effects
  • Polysaccharides / metabolism*
  • Polysaccharides / pharmacology*
  • RAW 264.7 Cells
  • Spectrophotometry, Ultraviolet / methods
  • Spectroscopy, Fourier Transform Infrared / methods
  • Tumor Necrosis Factor-alpha / biosynthesis
  • Tumor Necrosis Factor-alpha / metabolism


  • Anti-Inflammatory Agents
  • Polysaccharides
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide