title: Macrophage activation by polysaccharides from Atractylodes macrocephala Koidz through the nuclear factor-κB pathway.
abstract: BACKGROUND
  Atractylodes macrocephala Koidz is a traditional herb. Atractylodes macrocephalaon polysaccharides (AMP) have been found to enhance immunity and improve heart function. However, the mechanisms of the immunomodulatory effect have not been investigated.
  
  
  OBJECTIVE
  We examined whether AMP activated macrophages and explored the mechanisms of activation.
  
  
  METHODS
  AMP was prepared and evaluated its immunomodulatory activity (25, 50, 100, and 200 μg/mL) by detecting the phagocytosis and the production of tumor necrosis factor-α (TNF-α), IFN-γ, and nitric oxide (NO) in RAW264.7 macrophages. Furthermore, the role of nuclear factor-κB (NF-κB) pathway was examined in regulating TNF-α and NO production.
  
  
  RESULTS
  The phagocytosis of macrophages was enhanced by AMP in a dose-dependent manner and the maximal phagocytosis of macrophages occurred at concentrations of 100 and 200 μg/mL. NO, TNF-α, and IFN-γ release was also found to be dose dependent by increasing concentrations of AMP and reached the peak at a concentration of 200 μg/mL. In addition, AMP induced inhibitor kappaB (IκB) degradation and the activation of NF-κB by p65 nuclear translocation, and then the activation of NF-κB in nucleus peaked at a concentration of 200 μg/mL. Besides, NF-κB-specific inhibitor pyrrolidine dithiocarbamate (PDTC) decreased AMP-induced NO and TNF-α production.
  
  
  CONCLUSIONS
  These data suggest that AMP may modulate macrophage activities by stimulating NF-κB or activating NF-κB-dependent mechanisms.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou , China and.
authors.forename: Guang-Quan
authors.initials: GQ
authors.lastname: Ji
authors.forename: Ren-Qiong
authors.initials: RQ
authors.lastname: Chen
authors.forename: Jian-Xian
authors.initials: JX
authors.lastname: Zheng
mesh_terms: D000818:Animals; D031174:Atractylodes / Q000737:chemistry*; D015153:Blotting, Western; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000302:isolation & purification / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D007155:Immunologic Factors / Q000302:isolation & purification / Q000494:pharmacology*; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000096:biosynthesis; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D015398:Signal Transduction; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism
chemical_list: D004365:Drugs, Chinese Herbal; D007155:Immunologic Factors; D016328:NF-kappa B; D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma
keywords: Nitric oxide; nuclear factor-κB; tumor necrosis factor-α