Effects of berberine and cinnamic acid on palmitic acid-induced intracellular triglyceride accumulation in NIT-1 pancreatic β cells

Chin J Integr Med. 2016 Jul;22(7):496-502. doi: 10.1007/s11655-014-1986-0. Epub 2014 Dec 9.

Abstract

Objective: To investigate the effects of berberine (BBR) and cinnamic acid (CA), the main active components in Jiaotai Pill (, JTP), on palmitic acid (PA)-induced intracellular triglyceride (TG) accumulation in NIT-1 pancreatic β cells.

Methods: Cells were incubated in culture medium containing PA (0.25 mmol/L) for 24 h. Then treatments with BBR (10 μmol/L), CA (100 μmol/L) and the combination of BBR and CA (BBR+CA) were performed respectively. Intracellular lipid accumulation was assessed by Oil Red O staining and TG content was measured by colorimetric assay. The expression of adenosine monophosphate-activated protein kinase (AMPK) protein and its downstream lipogenic and fatty acid oxidation genes, including fatty acid synthase (FAS), acetyl-coA carboxylase (ACC), phosphorylation acetyl-coA carboxylase (pACC), carnitine acyl transferase 1 (CPT-1) and sterol regulating element binding protein 1c (SREBP-1c) were determined by Western blot or real time polymerase chain reaction.

Results: PA induced an obvious lipid accumulation and a significant increase in intracellular TG content in NIT-1 cells. PA also induced a remarkable decrease in AMPK protein expression and its downstream targets such as pACC and CPT-1. Meanwhile, AMPK downstream lipogenic genes including SREBP-1c mRNA, FAS and ACC protein expressions were increased. Treatments with BBR and BBR+CA, superior to CA, significantly reversed the above genes changes in NIT-1 pancreatic β cells. However, the synergistic effect of BBR and CA on intracellular TG content was not observed in the present study.

Conclusion: It can be concluded that in vitro, BBR and BBR+CA could inhibit PA-induced lipid accumulation by decreasing lipogenesis and increasing lipid oxidation in NIT-1 pancreatic β cells.

Keywords: Chinese medicine; Jiaotai Pill; NIT-1 cells; berberine; cinnamic acid; lipid; palmitic acid.

MeSH terms

  • AMP-Activated Protein Kinases / metabolism
  • Animals
  • Berberine / chemistry
  • Berberine / pharmacology*
  • Cell Line
  • Cinnamates / chemistry
  • Cinnamates / pharmacology*
  • Fatty Acids / metabolism
  • Gene Expression Regulation / drug effects
  • Insulin-Secreting Cells / drug effects
  • Insulin-Secreting Cells / metabolism*
  • Intracellular Space / metabolism*
  • Lipogenesis / drug effects
  • Lipogenesis / genetics
  • Mice
  • Oxidation-Reduction / drug effects
  • Palmitic Acid / toxicity*
  • Triglycerides / metabolism*

Substances

  • Cinnamates
  • Fatty Acids
  • Triglycerides
  • Berberine
  • cinnamic acid
  • Palmitic Acid
  • AMP-Activated Protein Kinases