Hydroxytyrosol promotes mitochondrial biogenesis and mitochondrial function in 3T3-L1 adipocytes

J Nutr Biochem. 2010 Jul;21(7):634-44. doi: 10.1016/j.jnutbio.2009.03.012. Epub 2009 Jul 2.

Abstract

Hydroxytyrosol (HT) in extra-virgin olive oil is considered one of the most important polyphenolic compounds responsible for the health benefits of the Mediterranean diet for lowering incidence of cardiovascular disease, the most common and most serious complication of diabetes. We propose that HT may prevent these diseases by a stimulation of mitochondrial biogenesis that leads to enhancement of mitochondrial function and cellular defense systems. In the present study, we investigated effects of HT that stimulate mitochondrial biogenesis and promote mitochondrial function in 3T3-L1 adipocytes. HT over the concentration range of 0.1-10 micromol/L stimulated the promoter transcriptional activation and protein expression of peroxisome proliferator-activated receptor (PPAR) coactivator 1 alpha (PPARGC1 alpha, the central factor for mitochondrial biogenesis) and its downstream targets; these included nuclear respiration factors 1 and 2 and mitochondrial transcription factor A, which leads to an increase in mitochondrial DNA (mtDNA) and in the number of mitochondria. Knockdown of Ppargc1 alpha by siRNA blocked HT's stimulating effect on Complex I expression and mtDNA copy number. The HT treatment resulted in an enhancement of mitochondrial function, including an increase in activity and protein expression of Mitochondrial Complexes I, II, III and V; increased oxygen consumption; and a decrease in free fatty acid contents in the adipocytes. The mechanistic study of the PPARGC1 alpha activation signaling pathway demonstrated that HT is an activator of 5'AMP-activated protein kinase and also up-regulates gene expression of PPAR alpha, CPT-1 and PPAR gamma. These data suggest that HT is able to promote mitochondrial function by stimulating mitochondrial biogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • AMP-Activated Protein Kinases / metabolism
  • Adipocytes / drug effects*
  • Adipocytes / enzymology
  • Adipocytes / physiology
  • Animals
  • Cardiovascular Diseases / diet therapy
  • Cardiovascular Diseases / drug therapy
  • Cardiovascular Diseases / prevention & control
  • Cell Respiration / drug effects
  • DNA, Mitochondrial / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Enzyme Activation / drug effects
  • Fatty Acids, Nonesterified / metabolism
  • Gene Expression Regulation / drug effects
  • Mice
  • Mitochondria / drug effects*
  • Mitochondria / enzymology
  • Mitochondria / physiology
  • Mitochondrial Proteins / genetics
  • Mitochondrial Proteins / metabolism
  • Nuclear Respiratory Factors / genetics
  • Nuclear Respiratory Factors / metabolism
  • Osmolar Concentration
  • Oxidative Phosphorylation / drug effects
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Peroxisome Proliferator-Activated Receptors / genetics
  • Peroxisome Proliferator-Activated Receptors / metabolism
  • Phenylethyl Alcohol / analogs & derivatives*
  • Phenylethyl Alcohol / pharmacology
  • RNA, Messenger / metabolism
  • RNA, Small Interfering
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • DNA, Mitochondrial
  • DNA-Binding Proteins
  • Fatty Acids, Nonesterified
  • Mitochondrial Proteins
  • Nuclear Respiratory Factors
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Peroxisome Proliferator-Activated Receptors
  • Ppargc1a protein, mouse
  • RNA, Messenger
  • RNA, Small Interfering
  • Trans-Activators
  • Transcription Factors
  • mitochondrial transcription factor A
  • 3,4-dihydroxyphenylethanol
  • AMP-Activated Protein Kinases
  • Phenylethyl Alcohol