Scopolin ameliorates high-fat diet induced hepatic steatosis in mice: potential involvement of SIRT1-mediated signaling cascades in the liver

Sci Rep. 2017 May 22;7(1):2251. doi: 10.1038/s41598-017-02416-6.

Abstract

The present study aimed to investigate whether scopolin exhibits beneficial effects on high-fat diet (HFD)-induced hepatic steatosis in mice. The involvement of sirtuin 1 (SIRT1) as a molecular target for scopolin was also explored. Scopolin decreased the Km of SIRT1 for p53 and nicotinamide adenine dinucleotide without altering Vmax in a cell-free system. Scopolin alleviated oleic acid-induced lipid accumulation and downregulation of SIRT1 activity in HepG2 cells, and these beneficial effects of scopolin were abolished in the presence of SIRT1 inhibitor. Mice administered 0.02% scopolin for 8 weeks exhibited improved phenotypes of HFD-induced hepatic steatosis along with increased hepatic SIRT1 activity and protein expression. Scopolin resulted in increased deacetylation of sterol regulatory element-binding protein 1c with subsequent downregulation of lipogenic genes, and enhanced deacetylation of protein peroxisome proliferator-activated receptor-γ coactivator 1α with upregulation of fatty acid oxidation genes in livers. Scopolin also enhanced deacetylation of nuclear factor-kappa enhancer binding protein and liver kinase B1 (LKB1), facilitating LKB1/AMP-activated protein kinase signaling cascades. Scopolin attenuated hepatic steatosis through activation of SIRT1-mediated signaling cascades, a potent regulator of lipid homeostasis. Increased hepatic SIRT1 activity and protein expression appeared to be associated with these beneficial effects of scopolin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Coumarins / chemistry
  • Coumarins / pharmacology*
  • Diet, High-Fat* / adverse effects
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Enzyme Activation / drug effects
  • Fatty Liver / drug therapy
  • Fatty Liver / etiology*
  • Fatty Liver / metabolism*
  • Fatty Liver / pathology
  • Glucosides / chemistry
  • Glucosides / pharmacology*
  • Lipid Metabolism / drug effects
  • Lipogenesis / drug effects
  • Magnetic Resonance Spectroscopy
  • Mice
  • Signal Transduction / drug effects*
  • Sirtuin 1 / metabolism*

Substances

  • Coumarins
  • Glucosides
  • scopolin
  • Sirtuin 1