Water-soluble and alkali-soluble polysaccharides from bitter melon inhibited lipid accumulation in HepG2 cells and Caenorhabditis elegans

Int J Biol Macromol. 2021 Jan 1:166:155-165. doi: 10.1016/j.ijbiomac.2020.10.128. Epub 2020 Oct 22.

Abstract

Bitter melon polysaccharides (BPS) have been reported to have hypolipidemic effects. However, the precise mechanism of BPS regulating lipid metabolism remains elusive. Water-soluble (WBPS) and alkali-soluble bitter melon polysaccharides (ABPS) were extracted to evaluate the fat-lowering bioactivities in HepG2 cells and Caenorhabditis elegans. WBPS and ABPS were slightly different in the uronic acid contents (22.23% and 5.69%), monosaccharide composition, molecular weight (Mw: 332 kDa and 1552 kDa, respectively) and IR spectra. In palmitic acid-treated HepG2 cell, the ABPS exhibited better effects on accelerating glucose consumption and decreasing the triglyceride content than WBPS via stimulating glucose consumption (GLUT4) and gluconeogenesis (PEPCK). In the model of glucose-treated C. elegans, we observed that both WBPS and ABPS obviously suppressed the fat accumulation, more significantly by ABPS, along with no toxicity towards some physical activities. Fat-5, fat-6 and fat-7 mediated fatty acid desaturases pathways were further confirmed to be involved in the lipid-lowering effects of BPSs. Our studies demonstrated that both WBPS and ABPS can exhibit effects on fat- lowering in HepG2 cells and C. elegans.

Keywords: Bitter melon polysaccharides; C. elegans; HepG2 cells; Lipid accumulation.

MeSH terms

  • Alkalies / chemistry
  • Animals
  • Caenorhabditis elegans
  • Caenorhabditis elegans Proteins / metabolism
  • Cucurbitaceae / chemistry*
  • Gluconeogenesis / drug effects
  • Glucose / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Hep G2 Cells
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Hypolipidemic Agents / chemistry*
  • Hypolipidemic Agents / pharmacology
  • Lipid Metabolism / drug effects*
  • Polysaccharides / chemistry*
  • Polysaccharides / pharmacology
  • Solubility
  • Stearoyl-CoA Desaturase / metabolism
  • Triglycerides / metabolism
  • Uronic Acids / chemistry

Substances

  • Alkalies
  • Caenorhabditis elegans Proteins
  • Glucose Transporter Type 4
  • Hypolipidemic Agents
  • Polysaccharides
  • SLC2A4 protein, human
  • Triglycerides
  • Uronic Acids
  • Stearoyl-CoA Desaturase
  • Glucose