Astragalus membranaceus Extract Attenuates Inflammation and Oxidative Stress in Intestinal Epithelial Cells via NF-κB Activation and Nrf2 Response

Int J Mol Sci. 2018 Mar 10;19(3):800. doi: 10.3390/ijms19030800.


Astragalus membranaceus, dried root extract, also known as Astragali radix, is used in traditional Chinese medicine as a tonic remedy. Moreover, it has been reported that Astragalus membranaceus could attenuate intestinal inflammation; however, the underlying mechanism for its anti-inflammatory activity in intestinal epithelial cells (IECs) remains unclear. In this study, we evaluated Astragalus membranaceus extract (5-100 µg/mL) in a model of inflammation and oxidative stress for IECs. We showed that Astragalus membranaceus extract reduced the inflammatory response induced by lipopolysaccharide from E. coli (LPS) plus interferon-γ (IFN), decreasing tumor necrosis factor-α (TNF-α) release, cycloxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, nitrotyrosine formation, nuclear factor-κB (NF-κB) activation, and reactive oxygen species (ROS) release in the non-tumorigenic intestinal epithelial cell line (IEC-6). The antioxidant potential of Astragalus membranaceus extract was also evaluated in a model of hydrogen peroxide (H₂O₂)-induced oxidative stress in IEC-6, indicating that this extract reduced ROS release and increased nuclear factor (erythroid-derived 2)-like 2 (Nrf2) activation and the expression of antioxidant cytoprotective factors in these cells. The results contributed to clarify the mechanisms involved in Astragalus membranaceus extract-reduced inflammation and highlighted the potential use of this extract as an anti-inflammatory and antioxidant remedy for intestinal diseases.

Keywords: Astragalus membranaceus; inflammation; intestinal epithelial cells; oxidative stress.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Astragalus propinquus / chemistry*
  • Cell Line
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • Enterocytes / drug effects*
  • Enterocytes / metabolism
  • Interferon-gamma / genetics
  • Interferon-gamma / metabolism
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism*
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Nitric Oxide Synthase Type II / genetics
  • Nitric Oxide Synthase Type II / metabolism
  • Oxidative Stress*
  • Plant Extracts / pharmacology*
  • Rats
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism


  • Anti-Inflammatory Agents
  • NF-E2-Related Factor 2
  • NF-kappa B
  • Plant Extracts
  • Tumor Necrosis Factor-alpha
  • Interferon-gamma
  • Nitric Oxide Synthase Type II
  • Cyclooxygenase 2
  • Ptgs2 protein, rat