Silibinin ameliorates steatosis and insulin resistance during non-alcoholic fatty liver disease development partly through targeting IRS-1/PI3K/Akt pathway

Int Immunopharmacol. 2013 Nov;17(3):714-20. doi: 10.1016/j.intimp.2013.08.019. Epub 2013 Sep 13.

Abstract

Silibinin (SIL) is a well-studied hepato-protective agent against a spectrum of liver diseases. However, the role of SIL in non-alcoholic fatty liver disease (NAFLD) induced insulin resistance and underlying signaling is not fully characterized. In this study, Sprague-Dawley (SD) rats were fed with high-fat diet to develop NAFLD with or without an SIL co-treatment. NAFLD rats showed typical NAFLD symptoms including histological changes, insulin resistance, and glucose metabolism dysfunction. SIL co-treatment significantly ameliorated these pathological features partly through restoring the IRS-1/PI3K/Akt pathway. In addition, BRL-3A and HepG2 cells were incubated with palmitic acid (PA) to induce steatosis. SIL co-treatment in cells also reduced lipid accumulation, recovered cell viability, and down-regulated the protein expression of resistin, the marker for insulin resistance. Specific blocker of PI3K abolished the ameliorative effects of SIL on cellular steatosis. In conclusion, SIL alleviated steatosis and insulin resistance both in vivo and in vitro partly through regulating the IRS-1/PI3K/Akt pathway.

Keywords: Insulin resistance; NAFLD; Signaling pathway; Silibinin.

MeSH terms

  • Alanine Transaminase / blood
  • Animals
  • Aspartate Aminotransferases / blood
  • Cell Line
  • Cell Line, Tumor
  • Diet, High-Fat
  • Fatty Liver / drug therapy
  • Fatty Liver / metabolism*
  • Glucose / metabolism
  • Humans
  • Insulin Receptor Substrate Proteins / metabolism
  • Insulin Resistance / physiology*
  • Male
  • Non-alcoholic Fatty Liver Disease
  • Phosphatidylinositol 3-Kinases / metabolism
  • Protective Agents / pharmacology*
  • Protective Agents / therapeutic use
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Silybin
  • Silymarin / pharmacology*
  • Silymarin / therapeutic use

Substances

  • Insulin Receptor Substrate Proteins
  • Irs1 protein, rat
  • Protective Agents
  • Silymarin
  • Silybin
  • Aspartate Aminotransferases
  • Alanine Transaminase
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-akt
  • Glucose