Low Molecular Pectin Inhibited the Lipid Accumulation by Upregulation of METTL7B

Appl Biochem Biotechnol. 2021 May;193(5):1469-1481. doi: 10.1007/s12010-021-03486-z. Epub 2021 Jan 23.


Inhibition of lipid accumulation is the key step to prevent nonalcoholic fatty liver (NAFL) progressing to nonalcoholic steatohepatitis. We aimed to study the effect of low-molecular-weight citrus pectin (LCP) against lipid accumulation and the underlying mechanism. Oleic acid (OA)-induced lipid deposition in HepG2 cells was applied to mimic in vitro model of lipid accumulation. Oil Red O (ORO) stain result showed lipid accumulation was significantly reduced, and levels of adipose triglyceride lipase (ATGL) and carnitine palmitoyltransferase-1 (CPT-1), involved in triacylglycerol catabolism and fatty acid β-oxidation, detected by RT-qPCR were increased after OA-stimulated HepG2 cells treated with LCP. RNA sequencing analysis identified 740 differentially expressed genes (DEGs) in OA-stimulated HepG2 cells treated with the LCP group (OA+LCP group), and bioinformatics analysis indicated that some DEGs were enriched in lipid metabolism-related processes and pathways. The expression of the top 8 known DEGs in the OA+LCP group was then verified by RT-qPCR, which showed that fold change (abs) of METTL7B was the highest among the 8 candidates. In addition, overexpression of METTL7B in HepG2 cells significantly inhibited the lipid accumulation and enhanced levels of ATGL and CPT-1. In conclusion, LCP inhibited lipid accumulation through the upregulation of METTL7B, and further enhancement of ATGL and CPT-1 levels. LCP is expected to develop as a promising agent to ameliorate fat accumulation in NAFL.

Keywords: ATGL; CPT-1; Lipid accumulation; Low molecular pectin; METTL7B.

MeSH terms

  • Carnitine Acyltransferases / metabolism
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Computational Biology
  • Hep G2 Cells
  • Humans
  • Lipase / metabolism
  • Lipid Metabolism / drug effects
  • Pectins / pharmacology*


  • Carrier Proteins
  • METTL7B protein, human
  • Pectins
  • Carnitine Acyltransferases
  • carnitine octanoyltransferase
  • Lipase
  • PNPLA2 protein, human