Inhibition of human gastric carcinoma cell growth in vitro by a polysaccharide from Aster tataricus

Int J Biol Macromol. 2012 Nov;51(4):509-13. doi: 10.1016/j.ijbiomac.2012.06.019. Epub 2012 Jun 19.

Abstract

A water-soluble polysaccharide (WATP), with a molecular weight of 6.3 × 10⁴ Da, was isolated from Aster tataricus. According to gas chromatography (GC) analysis, WATP was composed of galactose, glucose, fucose, rhamnose, arabinose and mannose with molar ratios of 2.1:1.3:0.9:0.5:0.3:0.6. The effects of WATP on cell proliferation and apoptosis in human gastric cancer SGC-7901 cells were examined. MTT assay showed that WATP had a perfectly tumor growth inhibitory activity on SGC-7901 cells, but no cytotoxicity on SGC-7901 and primary human polymorphonuclear (PMN) cells analyzed using LDH assay. Flow cytometry analysis indicated that WATP could significantly induce apoptosis of SGC-7901 cells. Furthermore using Rh123 and Fluo-3 as fluorescent probes, respectively, it was found that mitochondrial transmembrane potential (ΔΨ(m)) of treatment groups was significantly lower than that in un-treatment group and the concentration of calcium in cells exposed to WATP for 24 h was increased in a dose dependent manner compared with unexposed group. These results suggest that WATP induces apoptosis of SGC-7901 cells through calcium- and ΔΨ(m)-dependent pathways, indicating that it is potentially useful as a natural anti-cancer agent.

MeSH terms

  • Apoptosis / drug effects
  • Aster Plant / chemistry*
  • Calcium / metabolism
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Humans
  • Intracellular Space / drug effects
  • Intracellular Space / metabolism
  • Membrane Potential, Mitochondrial / drug effects
  • Polysaccharides / chemistry
  • Polysaccharides / pharmacology*
  • Solubility
  • Stomach Neoplasms / pathology*
  • Water / chemistry

Substances

  • Polysaccharides
  • Water
  • Calcium