Pu-erh tea attenuates hyperlipogenesis and induces hepatoma cells growth arrest through activating AMP-activated protein kinase (AMPK) in human HepG2 cells

J Agric Food Chem. 2009 Jun 24;57(12):5257-64. doi: 10.1021/jf900730e.

Abstract

In the present study, we successively extracted the pu-erh raw tea with methanol (PR-1), chloroform (PR-2), ethyl acetate (PR-3), n-butanol (PR-4), and water (PR-5). Among these extracts, PR-3 extract contained ingredients with the most effective hypolipidemic potential and was further purified by column chromatography. Moreover, chronic administration of PR-3 provoked a significant reduction in levels of serum triglyceride and low-density lipoprotein (LDL) in rats. Our study demonstrated that fraction 5 from the PR-3 extract (PR-3-5s) showed a hypolipidemic effect in human hepatoma HepG2 cells. PR-3-5s decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Moreover, PR-3-5s blocked the progression of the cell cycle at the G1 phase by inducing p53 expression and in turn upregulating p21 expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / genetics
  • AMP-Activated Protein Kinases / metabolism*
  • Animals
  • Cardiovascular Diseases / drug therapy
  • Cardiovascular Diseases / enzymology
  • Cardiovascular Diseases / metabolism*
  • Cardiovascular Diseases / physiopathology
  • Cell Cycle / drug effects
  • Cell Line
  • Cell Proliferation / drug effects*
  • Enzyme Activation / drug effects
  • Humans
  • Lipogenesis / drug effects*
  • Male
  • Models, Animal
  • Plant Extracts / administration & dosage
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Tea / chemistry*

Substances

  • Plant Extracts
  • Tea
  • AMP-Activated Protein Kinases