Structural characterization of a polysaccharide from the flower buds of Tussilago farfara, and its effect on proliferation and apoptosis of A549 human non-small lung cancer cell line

Int J Biol Macromol. 2018 Jul 1;113:849-858. doi: 10.1016/j.ijbiomac.2018.03.005. Epub 2018 Mar 2.

Abstract

In present study, we purified a polysaccharide, TFPB1, from the flower buds of Tussilago farfara using DEAE-cellulose 52 anion-exchange and Sephacryl S-300 HR gel filtration chromatography. TFPB1 was a homogeneous polysaccharide with a molecular weight of 37.8kDa and composed of rhamnose, galacturonic acid, glucose, galactose, and arabinose, in a ratio of 13:13:1:7:12. Methylation and NMR results demonstrated that TFPB1 contained a rhamnogalacturonan I backbone consisting of a repeat disaccharide unit →4)-α-D-GalAp-(1→2)-α-L-Rhap-(1→, substituted by various type II arabinogalactan branches including terminal galactose, (1→3)-β-D-galactan and (1→5)-α-L-arabinan, attached to the O-4 of (1→2)-α-L-Rhap. TFPB1 was found to inhibit cell proliferation of A549 cells and induce cell apoptosis in vitro. Furthermore, TFPB1 downregulated the phosphorylation of Akt, and upregulated caspase-3, Fas, FasL, and Bax expression, but downregulated Bcl-2 expression. Therefore, TFPB1 exhibited anti-proliferative and anti-apoptotic effect partly depending on the suppression of Akt signaling pathway. These findings provided us a potential chemotherapeutic strategy for the treatment of human non-small cell lung cancer.

Keywords: Lung cancer; Polysaccharide; Tussilago farfara L..

MeSH terms

  • A549 Cells
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology
  • Apoptosis / drug effects*
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Cell Cycle / drug effects
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Flowers / chemistry*
  • Humans
  • Lung Neoplasms / pathology*
  • Molecular Weight
  • Phosphatidylinositol 3-Kinases / metabolism
  • Polysaccharides / chemistry*
  • Polysaccharides / pharmacology*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Signal Transduction / drug effects
  • Tussilago / chemistry*

Substances

  • Antineoplastic Agents
  • Polysaccharides
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-akt