title: Proteomic analysis of endothelial lipid rafts reveals a novel role of statins in antioxidation.
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.
authors.affiliation: Department of Physiology and Pathophysiology, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Peking University Health Science Center, Beijing, 100191, China.
authors.forename: Ming-Xia
authors.initials: MX
authors.lastname: Gu
authors.forename: Yi
authors.initials: Y
authors.lastname: Fu
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Sun
authors.forename: Yu-Zhu
authors.initials: YZ
authors.lastname: Ding
authors.forename: Cheng-Hong
authors.initials: CH
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Pang
authors.forename: Songqin
authors.initials: S
authors.lastname: Pan
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhu
mesh_terms: D000595:Amino Acid Sequence; D000975:Antioxidants / Q000378:metabolism*; D000069059:Atorvastatin; D006538:Heptanoic Acids / Q000494:pharmacology; D061307:Human Umbilical Vein Endothelial Cells / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D008562:Membrane Glycoproteins / Q000032:analysis / Q000378:metabolism; D021962:Membrane Microdomains / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000032:analysis / Q000378:metabolism; D019704:Protein Disulfide-Isomerases / Q000032:analysis / Q000378:metabolism; D011506:Proteins / Q000032:analysis / Q000145:classification / Q000378:metabolism; D020543:Proteome / Q000032:analysis / Q000187:drug effects / Q000378:metabolism*; D011758:Pyrroles / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000032:analysis / Q000378:metabolism; D015203:Reproducibility of Results
chemical_list: D000975:Antioxidants; D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D008562:Membrane Glycoproteins; D011506:Proteins; D020543:Proteome; D011758:Pyrroles; D017382:Reactive Oxygen Species; D000069059:Atorvastatin; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; D019704:Protein Disulfide-Isomerases; C480743:TXNDC5 protein, human