Proteomic analysis of endothelial lipid rafts reveals a novel role of statins in antioxidation

J Proteome Res. 2012 Apr 6;11(4):2365-73. doi: 10.1021/pr300098f. Epub 2012 Mar 27.

Abstract

As inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase, statins have pleiotropic vascular-protective effects, such as anti-inflammatory and antioxidative effects. We investigated the short-term beneficial effects of statins on modulating the translocation of lipid-raft-related proteins in endothelial cells (ECs). Human umbilical vein ECs were treated with atorvastatin for 30 min or 2 h; lipid-raft proteins were isolated and examined by quantitative proteome assay. Functional classification of identified proteins in lipid rafts revealed upregulated antioxidative proteins; downregulated proteins were associated with inflammation and cell adhesion. Among proteins verified by Western blot analysis, endoplasmic reticulum protein 46 (ERp46) showed increased level in lipid rafts with atorvastatin. Further, atorvastatin inhibited the activation of membrane-bound NADPH oxidase in both untreated and angiotensin II-treated ECs, as shown by reduced reactive oxygen species production. Co-immunoprecipitation and immunofluorescence experiments revealed that atorvastatin increased the association of ERp46 and Nox2, an NADPH oxidase isoform, in lipid rafts, thereby inhibiting Nox2 assembly with its regulatory subunits, such as p47phox and p67phox. Our results reveal a novel antioxidative role of atorvastatin by promoting the membrane translocation of ERp46 and its binding with Nox2 to inhibit Nox2 activity in ECs, which may offer another insight into the pleiotropic functions of statins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antioxidants / metabolism*
  • Atorvastatin
  • Heptanoic Acids / pharmacology
  • Human Umbilical Vein Endothelial Cells / chemistry
  • Human Umbilical Vein Endothelial Cells / metabolism
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / pharmacology*
  • Membrane Glycoproteins / analysis
  • Membrane Glycoproteins / metabolism
  • Membrane Microdomains / chemistry*
  • Membrane Microdomains / metabolism
  • Molecular Sequence Data
  • NADPH Oxidase 2
  • NADPH Oxidases / analysis
  • NADPH Oxidases / metabolism
  • Protein Disulfide-Isomerases / analysis
  • Protein Disulfide-Isomerases / metabolism
  • Proteins / analysis
  • Proteins / classification
  • Proteins / metabolism
  • Proteome / analysis
  • Proteome / drug effects
  • Proteome / metabolism*
  • Pyrroles / pharmacology
  • Reactive Oxygen Species / analysis
  • Reactive Oxygen Species / metabolism
  • Reproducibility of Results

Substances

  • Antioxidants
  • Heptanoic Acids
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Membrane Glycoproteins
  • Proteins
  • Proteome
  • Pyrroles
  • Reactive Oxygen Species
  • Atorvastatin
  • CYBB protein, human
  • NADPH Oxidase 2
  • NADPH Oxidases
  • Protein Disulfide-Isomerases
  • TXNDC5 protein, human