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An apple oligogalactan suppresses endotoxin-induced cyclooxygenase-2 expression by inhibition of LPS pathways

Yuhua Li1, Lei Fan, Yang Sun

  • 1Key Laboratory of Gastrointestinal Pharmacology of Chinese Materia Medica of the State Administration of Traditional Chinese Medicine, Collaborative Innovation Center for Chinese Medicine in Qinba Mountains, Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China; Department of Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China.

International Journal of Biological Macromolecules
|July 6, 2013
PubMed

Insights

Apple oligogalactan (AOG) inhibits inflammation and cyclooxygenase-2 (COX-2) in colon cancer cells. This suggests AOG may aid in preventing colorectal cancer (CRC) and treating colitis.

Area of Science:

  • Oncology
  • Molecular Biology
  • Nutrition Science

Background:

  • Colorectal cancer (CRC) is a significant global health concern.
  • Apples contain compounds with anti-inflammatory and anti-carcinogenic properties beneficial for CRC prevention.
  • Apple oligogalactan (AOG) is a component of apples with potential health benefits.

Purpose of the Study:

  • To investigate the inhibitory effect of AOG on lipopolysaccharide (LPS)-activated human colon carcinoma cells.
  • To explore the underlying mechanisms of AOG's action on inflammatory pathways.
  • To evaluate AOG's potential in CRC prevention and colitis treatment.

Main Methods:

  • Human colon carcinoma cell lines (HT-29 and SW-620) were treated with AOG and LPS.
  • Real-time PCR and Western blot were used to analyze gene and protein expression.
  • Electrophoretic mobility shift assay (EMSA) and ELISA assessed pathway activation.

Main Results:

  • AOG significantly inhibited cyclooxygenase-2 (COX-2) expression and activity in LPS-activated colon cancer cells.
  • AOG suppressed the phosphorylation of MAPKs and the activation of NF-κB and AP-1 pathways.
  • These mechanisms contribute to AOG's anti-inflammatory effects.

Conclusions:

  • AOG demonstrates inhibitory effects on key inflammatory mediators in colon cancer cells.
  • AOG's mechanisms involve the modulation of MAPK, NF-κB, and AP-1 signaling pathways.
  • AOG shows promise as a therapeutic agent for colitis and a preventative measure against colorectal cancer.
Keywords:
An apple oligogalactan (AOG)Cyclooxygenase-2 (COX-2)Lipopolysaccharide (LPS)

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