title: Native low density lipoprotein promotes lipid raft formation in macrophages.
abstract: Oxidized low‑density lipoprotein (LDL) has an important role in atherogenesis; however, the mechanisms underlying cell‑mediated LDL oxidation remain to be elucidated. The present study investigated whether native‑LDL induced lipid raft formation, in order to gain further insight into LDL oxidation. Confocal microscopic analysis revealed that lipid rafts were aggregated or clustered in the membrane, which were colocalized with myeloperoxidase (MPO) upon native LDL stimulation; however, in the presence of methyl‑β‑cyclodextrin (MβCD), LDL‑stimulated aggregation, translocation, and colocalization of lipid rafts components was abolished.. In addition, lipid raft disruptors MβCD and filipin decreased malondialdehyde expression levels. Density gradient centrifugation coupled to label‑free quantitative proteomic analysis identified 1,449 individual proteins, of which 203 were significantly upregulated following native‑LDL stimulation. Functional classification of the proteins identified in the lipid rafts revealed that the expression levels of translocation proteins were upregulated. In conclusion, the results of the present study indicated that native‑LDL induced lipid raft clustering in macrophages, and the expression levels of several proteins were altered in the stimulated macrophages, which provided novel insights into the mechanism underlying LDL oxidation.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Ling-Yan
authors.initials: LY
authors.lastname: Ping
authors.affiliation: Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
authors.forename: Duc M
authors.initials: DM
authors.lastname: Duong
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Gao
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: He
authors.affiliation: Department of Pathology and Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wei
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China.
authors.forename: Jun-Zhu
authors.initials: JZ
authors.lastname: Wu
mesh_terms: D000818:Animals; D015153:Blotting, Western; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D021962:Membrane Microdomains / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D010084:Oxidation-Reduction / Q000187:drug effects; D009195:Peroxidase / Q000378:metabolism; D020543:Proteome / Q000378:metabolism; D040901:Proteomics; D000067996:RAW 264.7 Cells; D015203:Reproducibility of Results
chemical_list: C491737:Erp29 protein, mouse; D006360:Heat-Shock Proteins; D008077:Lipoproteins, LDL; D008565:Membrane Proteins; D020543:Proteome; C106354:flotillins; D009195:Peroxidase